Tuesday, 30 September 2014

Complete Tips for CIE AS and A Level Examination

I got 4A for my AS Level in October 2013 and 4A* for my A Level in May 2014. The 4 subjects that I took were Mathematics, Chemistry, Physics and Biology. Do you want to know how to score in AS and A Level for these 4 subjects? Here, I am posting the complete tips for AS and A Level. These tips are intended for all students who are sitting for AS or A Level in October 2014, May 2015 or October 2015. Please click on the links below to view the tips for each subject.


AS & A Level Mathematics:

http://daniellimjj.blogspot.com/2014/10/tips-for-cie-as-and-level-mathematics.html


AS & A Level Chemistry:

http://daniellimjj.blogspot.com/2014/10/tips-for-cie-as-and-level-chemistry.html


AS & A Level Physics:

http://daniellimjj.blogspot.com/2014/10/tips-for-cie-as-and-level-physics.html


AS & A Level Biology:

http://daniellimjj.blogspot.com/2014/10/tips-for-cie-as-and-level-biology.html


For all other AS and A Level subjects, I do not take them, so I cannot give any tips. Ask someone else who scores well in the subject for tips.


If you are looking for tips for SPM examination, you can find it here:
http://daniellimjj.blogspot.com/2013/06/complete-tips-for-spm-examination-first.html

Tuesday, 9 September 2014

Tips for CIE AS and A Level Biology

I got 4A for my AS Level in October 2013 and 4A* for my A Level in May 2014. One of the 4 subjects I took was Biology. My percentage uniform mark for Biology was 90% in AS Level and 92% in A Level. Do you want to know how to score in AS and A Level for Biology? Here, I am posting the complete tips for AS and A Level Biology. These tips are intended for students who are sitting for AS or A Level in October 2014, May 2015 or October 2015.

Tips for other CIE AS and A Level subjects can be found here:
http://daniellimjj.blogspot.com/2014/09/complete-tips-for-cie-as-and-level.html


1. Studying tips
- When your teacher is teaching in class, pay attention to what your teacher says. Make sure you understand everything taught by your teacher. If you do not understand anything, ask your teacher or friends.
- You need notes or reference books that are complete. As far as I know, no reference books in the market is complete. Instead, I recommend you to use my notes. You can download my notes here:
http://daniellimjj.blogspot.com/2014/06/full-notes-for-cambridge-international.html . However, if you know of any reference book that is complete, you may use it.
- When studying a chapter, read through all the explanations in my notes or in the reference book sentence by sentence. Make sure that you truly understand each sentence before moving on to the next sentence. Certain topics may require understanding of earlier topics, so make sure you understand those topics. You should also try to relate them to what your teacher had taught in college or school.
- You should be actively involved in all experiments carried out in college or school because this can help improve your practical skills which are essential for Paper 3 and Paper 5.
- Then, you have to remember everything that you understood. You can memorise the sentences in my notes or in the reference book, or you can also create your own sentences that have the same meaning and memorise them. If you create your own sentences, make sure that you do not change the original meaning, do not leave out any important points and do not change the important keywords and scientific terms. However, do not just memorise without understanding. Once you have understood, it will be quite easy to remember and you will be unlikely to forget any of the points.
- For certain facts, there may be no explanation for them so it is not possible to understand them. In that case, you have to remember and memorise those facts.
- You have to regularly revise every topics again and again. When revising, go through all the explanation and facts in my notes or in the reference book. Make sure that you do not forget anything that you have understood previously. Regular and repeated revision will help you to remember all the explanation and facts for a long time.
- When you have understood all topics, you have to do past year A Level questions. They are available on
http://papers.xtremepapers.com/CIE/Cambridge%20International%20A%20and%20AS%20Level/ . After doing the questions, refer to the mark scheme and do self marking. The mark schemes can be found on the same website as the past year questions.
- You should understand how the mark schemes are used. In the mark schemes for Biology, most marks are independent of any other marks, which means that they can be scored without other marks also being scored, unless otherwise stated by the mark scheme. If any biological term is underlined or highlighted, it means that the exact term must be used in the answer and no other term is acceptable even if the meaning is the same, but grammatical variants of the term is accepted. If any non-biological term is underlined or highlighted, it means that either the exact term or other terms with the same meaning must be used in the answer. If any words are placed in brackets, it means that the words need not be present in the answer for the mark to be scored. In the mark schemes, A means accept, I means ignore while R means reject.
- When doing revision before exam, you should first go through the subtopics that you think is more difficult or that you may have forgotten. Then, go through other topics as well if possible.
- To prepare for Biology Paper 3 and Paper 5, you should go through all the past year questions and the mark schemes. Find out how every question is marked and which points need to be included in the answers. The pattern of questions set is similar for every year and you should familiarise yourself with the pattern. Usually, the same type of questions will have similar mark scheme, so this can help you when answering exam questions. You should remember the answers for questions that are common.

2. Paper 1
- Read the question and all the options carefully. Write any rough workings on the question paper if you need to. Cancel off the options that you consider as definitely wrong. Then, choose the most suitable answer among the options.

3. Paper 2 and Paper 4
- Paper 2 and Paper 4 Section A consists of structured questions where you must answer all questions while Paper 4 Section B consists of 2 essay questions where you can choose any one of them. You can answer both questions in Paper 4 Section B if you have time. The examiner will mark your answers for both questions and choose the one where you score higher marks.
- When answering, read the question and all information given carefully. Make sure that you know what the question is asking for. Answer the questions based on your knowledge and understanding on the relevant topic in Biology. Certain questions may test you on more than one topics. For some questions, you may have to apply what you have learnt in Biology in order to answer them. You have to think carefully and relate the question to what you have learnt. You may also be asked to give your own opinions.
- When writing your answer, you can use the same or similar words or sentences as those in my notes or in the reference books if possible. However, sometimes you may need to make some changes in order to suit the question. You can also answer in your own sentences that have the same meaning. If the question asks on something that is not in my notes and the reference books (the question requires you to apply what you have learnt in Biology or give your own opinion), then you have to answer in your own sentences. For all questions, your answer must be specific and not too general. Give the most suitable answer according to the question.
- You should use the correct biological terms in your answer. Do not replace them with other terms that are inappropriate, even if their meaning are the same. You should spell all biological terms correctly. If you can't do so, try to spell it in such a way where it sounds the same as the actual term when read out. Marks are usually not deducted for spelling errors in biological terms as long as it still sounds the same and that it is not easily confused with other terms. If you spell a non-biological term wrongly or if you make grammatical errors in your answer, marks will not be deducted for as long as the examiner can understand what you are writing. You are allowed to use suitable short forms in your answer, such as formula for chemical substances and symbols for units of physical quantities.
- It is not compulsory to answer in continuous writing form. You are allowed to answer in table form, point form or other suitable forms. In suitable cases, you can also use diagrams, equations or graphs in your answer.
- When answering questions on calculation, you should show all workings. You should not skip any important steps. You must also write the correct unit for the final answer if it is not provided. The number of marks allocated for the question usually shows the amount of working needed. 1 mark will be given for each important step and the final answer. Correct answer without working usually scores only 1 mark. If your final answer is wrong but some of your working is correct, you may still be given some marks. You are not allowed to write extra solutions or answers. If you do so and any of the answers or solutions is wrong, marks will be deducted. For a calculation question which requires you to use your answer from the previous question, even if your answer for the previous question is wrong and you use it for this question causing your answer for this question to be wrong, usually you will still get full marks for this question as long as your calculation for this question is correct. This is known as 'error carried forward'.
- When describing numerical data shown in a graph or table, you should quote suitable figures together with their units from the graph or table. For graph, each set of figure that you quote should include both the x value and y value and you should quote the figures accurate to half a small square.
- For questions that require explanation or description, your answer must be very detailed. You are advised to answer in complete sentences so that your answer can be easily understood. The number of marks allocated for the question usually shows the number of points needed in your answer. 1 mark is given for each correct point. Do not miss out any important points in your answer. You are allowed to write extra points in your answer, but you must be careful not to write any points that contradict one another. Marks will only be given for the correct points. For points that are not acceptable, whether they contain wrong facts or not, no mark will be given or deducted. However, for points that contradict one another, no mark will be given for both the points, even if one of them is correct. You are advised to write extra points if you are not completely sure of what the question is asking for.
- For questions that do not require explanation or description, write the answer straight away. You need not answer in complete sentences. The number of marks allocated for the question usually shows the number of answers needed. You are allowed to write extra answers, but you must be careful not to write answers that contradict one another. Marks will only be given for the correct answers. For answers that are not acceptable, whether they contain wrong facts or not, no mark will be given or deducted. However, for answers that contradict one another, no mark will be given for both the answers, even if one of them is correct.
- When drawing diagrams, make sure that all important details are included in the diagram you draw. You have to label correctly all parts in the diagram. Your diagram should be clear and neat.

4. Paper 3
- During the test, read the question and all information given carefully. Make sure that you understand the experiment given. Certain parts of the question require you to record the readings from the experiment in a table. You should draw the tables before carrying out the experiment so that you can record your readings in the table straight away during the experiment. Then, carry out the experiment by following the steps given in the question exactly. You need to apply your Biology practical skills when carrying out the experiment.
- Certain questions may require your knowledge and understanding in Biology to answer them. You may also need to give your own opinions. Your answer must be specific and not too general. Give the most suitable answer according to the question.
- When recording readings from an measuring instrument, the number of decimal places used should be equal to half of the smallest division of scale of the instrument (For example, if the instrument's smallest division of scale is 0.1, you should record the reading to the nearest 0.05, which is 2 decimal places.) For digital instruments (except digital stopwatch), the number of decimal places used should be the same as that shown on the display. The reading should be recorded to the nearest 1s for stopwatch (both analogue and digital). In all cases, do not give more or less number of decimal places. You must also write the correct units.
- When plotting graph, draw both the horizontal and vertical axis on the graph paper correctly. You should plot the independent variable on the x-axis and dependent variable on the y-axis. Label both axis correctly and state the unit (if any). Use a suitable scale for both axis and do not use any odd scales such as 3:10. Both the x-axis and y-axis need not start from 0 (unless otherwise stated by the question). The scales should be chosen such that the graph cover at least half of the graph paper. For line graphs, the markings on the scales should be 2cm apart, plot all points on the graph accurate to half a small square and the diameter of each point should not be larger than half a small square, then draw a curve or straight line that passes through all points on the graph if it is possible to do so, or if it is not possible, you can just use straight lines to join them point-to-point, and in all cases never extrapolate the line. For bar charts, draw blocks with equal width accurate to half a small square, where there must be space between the blocks and the distance between adjacent blocks should be equal, then label every block. After that, draw the error bars based on the standard error or standard deviation if required by the question.
- For questions on microscopy, you will be required to draw plan diagrams and high power drawings. For all drawings, use pencil to draw, draw as big as possible without drawing over the text of the question and leave enough space for labels, ensure that the lines you draw are thin, single, unbroken, clear & continuous and never shade or colour. When drawing plan diagrams, show the outlines of the tissues, ensure that the proportions of tissues in the diagram you draw is the same as what you see and do not include drawings of cells. When drawing high power drawings, draw only what the question asks, show the outlines of the cells, ensure that the proportions of cells in the diagram you draw is the same as what you see, show the cell walls of plant cells as double lines and where plant cells touch there should be 3 lines and show any contents of cells that you can see which may be nucleus, chloroplasts, vacuoles or others. Label your diagram if required by the question. Use a ruler to draw the labelling lines.
- For any questions involving calculation, the number of significant figures of your answer should be equal to the number of significant figures of the raw value used in the calculation with the least number of significant figures. You should show all workings and do not skip any important steps. You must also write the correct unit for the final answer if it is not provided. You are not allowed to write extra solutions or answers. If you do so and any of the answers or solutions is wrong, marks will be deducted. For a calculation question which requires you to use your answer from the previous question, even if your answer for the previous question is wrong and you use it for this question causing your answer for this question to be wrong, usually you will still get full marks for this question as long as your calculation for this question is correct. This is known as 'error carried forward'.
- For questions that require explanation or description, your answer must be very detailed. You are advised to answer in complete sentences so that your answer can be easily understood. The number of marks allocated for the question usually shows the number of points needed in your answer. 1 mark is given for each correct point. Do not miss out any important points in your answer. You are allowed to write extra points in your answer, but you must be careful not to write any points that contradict one another. Marks will only be given for the correct points. For points that are not acceptable, whether they contain wrong facts or not, no mark will be given or deducted. However, for points that contradict one another, no mark will be given for both the points, even if one of them is correct. You are advised to write extra points if you are not completely sure of what the question is asking for.
- For questions that do not require explanation or description, write the answer straight away. You need not answer in complete sentences. The number of marks allocated for the question usually shows the number of answers needed. You are allowed to write extra answers, but you must be careful not to write answers that contradict one another. Marks will only be given for the correct answers. For answers that are not acceptable, whether they contain wrong facts or not, no mark will be given or deducted. However, for answers that contradict one another, no mark will be given for both the answers, even if one of them is correct.
- When drawing diagrams, make sure that all important details are included in the diagram you draw. You have to label correctly all parts in the diagram. Your diagram should be clear and neat.
- For all questions, you should use the correct experimental and biological terms in your answer. Do not replace them with other terms that are inappropriate, even if their meaning are the same. You should spell all experimental and biological terms correctly. If you can't do so, try to spell it in such a way where it sounds the same as the actual term when read out. Marks are usually not deducted for spelling errors in experimental and biological terms as long as it still sounds the same and that it is not easily confused with other terms. If you spell other terms wrongly or if you make grammatical errors in your answer, marks will not be deducted for as long as the examiner can understand what you are writing. You are allowed to use suitable short forms in your answer, such as formula for chemical substances and symbols for units of physical quantities.

5. Paper 5
- When answering, read the question and all information given carefully. Make sure that you understand the experiment given and know what the question is asking for. Answer the questions based on the experiment and its observations and results. You may need to apply your Biology experimental skills to answer some questions. Certain questions may require your knowledge and understanding in Biology to answer them. You may also need to give your own opinions. For all questions, your answer must be specific and not too general. Give the most suitable answer according to the question.
- You should use the correct biological and experimental terms in your answer. Do not replace them with other terms that are inappropriate, even if their meaning are the same. You should spell all biological and experimental terms correctly. If you can't do so, try to spell it in such a way where it sounds the same as the actual term when read out. Marks are usually not deducted for spelling errors in biological and experimental terms as long as it still sounds the same and that it is not easily confused with other terms. If you spell other terms wrongly or if you make grammatical errors in your answer, marks will not be deducted for as long as the examiner can understand what you are writing. You are allowed to use suitable short forms in your answer, such as formula for chemical substances and symbols for units of physical quantities.
- It is not compulsory to answer in continuous writing form. You are allowed to answer in table form, point form or other suitable forms. In suitable cases, you can also use diagrams, equations or graphs in your answer.
- For any questions involving calculation, the number of significant figures of your answer should be equal to the number of significant figures of the raw value used in the calculation with the least number of significant figures. You should show all workings and do not skip any important steps. You must also write the correct unit for the final answer if it is not provided. You are not allowed to write extra solutions or answers. If you do so and any of the answers or solutions is wrong, marks will be deducted. For a calculation question which requires you to use your answer from the previous question, even if your answer for the previous question is wrong and you use it for this question causing your answer for this question to be wrong, usually you will still get full marks for this question as long as your calculation for this question is correct. This is known as 'error carried forward'.
- For questions that require explanation or description, your answer must be very detailed. You are advised to answer in complete sentences so that your answer can be easily understood. The number of marks allocated for the question usually shows the number of points needed in your answer. 1 mark is given for each correct point. Do not miss out any important points in your answer. You are allowed to write extra points in your answer, but you must be careful not to write any points that contradict one another. Marks will only be given for the correct points. For points that are not acceptable, whether they contain wrong facts or not, no mark will be given or deducted. However, for points that contradict one another, no mark will be given for both the points, even if one of them is correct. You are advised to write extra points if you are not completely sure of what the question is asking for.
- For questions that do not require explanation or description, write the answer straight away. You need not answer in complete sentences. The number of marks allocated for the question usually shows the number of answers needed. You are allowed to write extra answers, but you must be careful not to write answers that contradict one another. Marks will only be given for the correct answers. For answers that are not acceptable, whether they contain wrong facts or not, no mark will be given or deducted. However, for answers that contradict one another, no mark will be given for both the answers, even if one of them is correct.
- When drawing diagrams, make sure that all important details are included in the diagram you draw. You have to label correctly all parts in the diagram. Your diagram should be clear and neat.
- When plotting graph, draw both the horizontal and vertical axis on the graph paper correctly. You should plot the independent variable on the x-axis and dependent variable on the y-axis. Label both axis correctly and state the unit (if any). Use a suitable scale for both axis and do not use any odd scales such as 3:10. Both the x-axis and y-axis need not start from 0 (unless otherwise stated by the question). The scales should be chosen such that the graph cover at least half of the graph paper. For line graphs, the markings on the scales should be 2cm apart, plot all points on the graph accurate to half a small square and the diameter of each point should not be larger than half a small square, then draw a curve or straight line that passes through all points on the graph if it is possible to do so, or if it is not possible, you can just use straight lines to join them point-to-point, and in all cases never extrapolate the line. For bar charts, draw blocks with equal width accurate to half a small square, where there must be space between the blocks and the distance between adjacent blocks should be equal, then label every block. After that, draw the error bars based on the standard error or standard deviation if required by the question.
- For the question on planning experiment, when writing the procedure, you must include the steps to change the independent variable, measure the dependent variable and control the constant variable, as well as other steps required to set up the apparatus. You should also state the potential safety hazards when carrying out the experiment and the ways to avoid them. If there is no significant safety hazard, just state in your answer 'This is a low risk experiment'. Besides, you have to state the ways to improve the reliability of the experiment such as repeating the experiment and calculating the mean or identifying anomalies. In the procedure, you should state the amount and concentration of the substances used. You are advised to answer in complete sentences so that your answer can be easily understood. You do not need to draw the diagram of set-up apparatus.


Tips for other CIE AS and A Level subjects can be found here:
http://daniellimjj.blogspot.com/2014/09/complete-tips-for-cie-as-and-level.html

Monday, 8 September 2014

Tips for CIE AS and A Level Chemistry

I got 4A for my AS Level in October 2013 and 4A* for my A Level in May 2014. One of the 4 subjects I took was Chemistry. My percentage uniform mark for Chemistry was 96% in AS Level and 93% in A Level. Do you want to know how to score in AS and A Level for Chemistry? Here, I am posting the complete tips for AS and A Level Chemistry. These tips are intended for students who are sitting for AS or A Level in October 2014, May 2015 or October 2015.

Tips for other CIE AS and A Level subjects can be found here:

http://daniellimjj.blogspot.com/2014/09/complete-tips-for-cie-as-and-level.html


1. Studying tips
- When your teacher is teaching in class, pay attention to what your teacher says. Make sure you understand everything taught by your teacher. If you do not understand anything, ask your teacher or friends.
- You need notes or reference books that are complete. As far as I know, no reference books in the market is complete. Instead, I recommend you to use my notes. You can download my notes here:
http://daniellimjj.blogspot.com/2014/06/full-notes-for-cambridge-international.html . However, if you know of any reference book that is complete, you may use it.
- When studying a chapter, read through all the explanations in my notes or in the reference book sentence by sentence. Make sure that you truly understand each sentence before moving on to the next sentence. Certain topics may require understanding of earlier topics, so make sure you understand those topics. You should also try to relate them to what your teacher had taught in college or school.
- You should be actively involved in all experiments carried out in college or school because this can help improve your practical skills which are essential for Paper 3 and Paper 5.
- Then, you have to remember everything that you understood. You can memorise the sentences in my notes or in the reference book, or you can also create your own sentences that have the same meaning and memorise them. If you create your own sentences, make sure that you do not change the original meaning, do not leave out any important points and do not change the important keywords and scientific terms. However, do not just memorise without understanding. Once you have understood, it will be quite easy to remember and you will be unlikely to forget any of the points.
- For certain facts, there may be no explanation for them so it is not possible to understand them. In that case, you have to remember and memorise those facts.
- For the calculations, you need to know how to apply what you have learnt and use the correct formula to solve the questions. Go through all the example questions in my notes or in the reference book. Make sure that you understand how every question is solved.
- You have to regularly revise every topics again and again. When revising, go through all the explanation, facts and examples for calculation questions in my notes or in the reference book. Make sure that you do not forget anything that you have understood previously. Regular and repeated revision will help you to remember all the explanation and facts for a long time.
- When you have understood all topics, you have to do past year A Level questions. They are available on
http://papers.xtremepapers.com/CIE/Cambridge%20International%20A%20and%20AS%20Level/ . After doing the questions, refer to the mark scheme and do self marking. The mark schemes can be found on the same website as the past year questions.
- You should understand how the mark schemes are used. In the mark schemes for Chemistry, most marks are independent of any other marks, which means that they can be scored without other marks also being scored, unless otherwise stated by the mark scheme. If any Chemistry term is underlined or highlighted, it means that the exact term must be used in the answer and no other term is acceptable even if the meaning is the same, but grammatical variants of the term is accepted. If any non-Chemistry term is underlined or highlighted, it means that either the exact term or other terms with the same meaning must be used in the answer. If any words are placed in brackets, it means that the words need not be present in the answer for the mark to be scored. In the mark schemes, A means accept, I means ignore while R means reject.
- When doing revision before exam, you should first go through the subtopics that you think is more difficult or that you may have forgotten. Then, go through other topics as well if possible.
- To prepare for Chemistry Paper 3 and Paper 5, you should go through all the past year questions and the mark schemes. Find out how every question is marked and which points need to be included in the answers. The pattern of questions set is similar for every year and you should familiarise yourself with the pattern. Usually, the same type of questions will have similar mark scheme, so this can help you when answering exam questions. You should remember the answers for questions that are common.

2. Paper 1
- Read the question and all the options carefully. Write any rough workings on the question paper if you need to. Cancel off the options that you consider as definitely wrong. Then, choose the most suitable answer among the options.

3. Paper 2 and Paper 4
- When answering, read the question and all information given carefully. Make sure that you know what the question is asking for. Answer the questions based on your knowledge and understanding on the relevant topic in Chemistry. Certain questions may test you on more than one topics. For some questions, you may have to apply what you have learnt in Chemistry in order to answer them. You have to think carefully and relate the question to what you have learnt. You may also be asked to give your own opinions.
- When writing your answer, you can use the same or similar words or sentences as those in my notes or in the reference books if possible. However, sometimes you may need to make some changes in order to suit the question. You can also answer in your own sentences that have the same meaning. If the question asks on something that is not in my notes and the reference books (the question requires you to apply what you have learnt in Chemistry or give your own opinion), then you have to answer in your own sentences. For all questions, your answer must be specific and not too general. Give the most suitable answer according to the question.
- You should use the correct Chemistry terms in your answer. Do not replace them with other terms that are inappropriate, even if their meaning are the same. You should spell all Chemistry terms correctly. If you can't do so, try to spell it in such a way where it sounds the same as the actual term when read out. Marks are usually not deducted for spelling errors in Chemistry terms as long as it still sounds the same and that it is not easily confused with other terms. If you spell a non-Chemistry term wrongly or if you make grammatical errors in your answer, marks will not be deducted as long as the examiner can understand what you are writing. You are allowed to use suitable short forms in your answer, such as formula for chemical substances and symbols for units of physical quantities.
- It is not compulsory to answer in continuous writing form. You are allowed to answer in table form, point form or other suitable forms. In suitable cases, you can also use diagrams, equations or graphs in your answer.
- When answering questions on calculation, you should show all workings. You should not skip any important steps. You must also write the correct unit for the final answer if it is not provided. You are advised to write down the formula used to solve the question, even though it is not compulsory to do so. The number of marks allocated for the question usually shows the amount of working needed. 1 mark will be given for each important step and the final answer. Correct answer without working usually scores only 1 mark. If your final answer is wrong but some of your working is correct, you may still be given some marks. You are not allowed to write extra solutions or answers. If you do so and any of the answers or solutions is wrong, marks will be deducted. When copying figures from the question or from your answer for the previous part of the question, be careful not to copy wrongly. For a calculation question which requires you to use your answer from the previous question, even if your answer for the previous question is wrong and you use it for this question causing your answer for this question to be wrong, usually you will still get full marks for this question as long as your calculation for this question is correct. This is known as 'error carried forward'.
- Usually, you should give the final answer to 3 significant figures. Do not write your final answer as a fraction or in surd form. However, if the question asks you to give your answer to a specific number of significant figures, then you must follow the instruction, or if the question states that you must give your answer to a suitable number of significant figures, then the number of significant figures of your answer should be equal to the number of significant figures of the raw value used in the calculation with the least number of significant figures.
-  For questions that require explanation or description, your answer must be very detailed. You are advised to answer in complete sentences so that your answer can be easily understood. The number of marks allocated for the question usually shows the number of points needed in your answer. 1 mark is given for each correct point. Do not miss out any important points in your answer. You are allowed to write extra points in your answer, but you must be careful not to write any points with wrong facts. Marks will only be given for the correct points. For points that are irrelevant but does not contain wrong facts, no mark will be given or deducted. However, for points that contain wrong facts, marks may be deducted.
- For questions that do not require explanation or description, write the answer straight away. You need not answer in complete sentences. The number of marks allocated for the question usually shows the number of answers needed. If the question states the number of answers you have to write, then you are not allowed to write extra answers. If you do so, marks may not be given for the extra answers, and marks may be deducted if any of them is wrong. If the question does not state the number of answers you have to write, you are allowed to write extra answers, but you must be careful not to write any answer with wrong facts. Marks will only be given for the correct answers. For answers that are irrelevant but does not contain wrong facts, no mark will be given or deducted. However, for answers that contain wrong facts, marks may be deducted.
- When drawing diagrams, make sure that all important details are included in the diagram you draw. You have to label correctly all parts in the diagram. Your diagram should be clear and neat.

4. Paper 3
- During the test, read the question and all information given carefully. Make sure that you understand the experiment given. Certain parts of the question require you to record the readings from the experiment in a table. You should draw the tables before carrying out the experiment so that you can record your readings in the table straight away during the experiment. Then, carry out the experiment by following the steps given in the question exactly. You need to apply your Chemistry practical skills when carrying out the experiment.
- Certain questions may require your knowledge and understanding in Chemistry to answer them. You may also need to give your own opinions. Your answer must be specific and not too general. Give the most suitable answer according to the question.
- When recording readings from an measuring instrument, the number of decimal places used should be equal to half of the smallest division of scale of the instrument (For example, if the instrument's smallest division of scale is 0.1, you should record the reading to the nearest 0.05, which is 2 decimal places.) For digital instruments (except digital stopwatch), the number of decimal places used should be the same as that shown on the display. The reading should be recorded to the nearest 1s for stopwatch (both analogue and digital). In all cases, do not give more or less number of decimal places. You must also write the correct units.
- For questions on titration, you should first perform a rough titration, then perform 2 accurate titrations. Record the initial burette reading and final burette reading for each titration, then calculate the titre. You should record everything in a table. All readings should be recorded to 2 decimal places. The titre for the 2 accurate titrations should not differ by more than 0.10cm3. Then, calculate the mean titre for the 2 accurate titrations. The mean should be given to 2 decimal places.
- When plotting graph, draw both the horizontal and vertical axis on the graph paper correctly. Label both axis correctly and state the unit (if any). Use a suitable scale for both axis and do not use any odd scales such as 3:10. Both the x-axis and y-axis need not start from 0 (unless otherwise stated by the question). The scales should be chosen such that the points plotted on graph cover at least half of the graph paper. Plot all points on the graph accurately. The points should be accurate to half a small square. For all the points, their diameter should not be larger than half a small square. Then, draw the correct straight line or curve. When drawing the straight line or curve, it should pass through all points on the graph if possible. If this is not possible, the line or curve should pass through as many points on the graph as possible, all the points should be close to it and the number of points above and below the line or curve should be almost equal. When determining the gradient of a straight-line graph, choose 2 points on the line and draw a triangle. The distance between the 2 points chosen should be at least half the length of the line.
- For questions on qualitative analysis, for each chemical test, you should use about 1cm depth or 2cm3 of each solution unless otherwise stated by the question. You have to record the full observations. State if there is any colour change or if precipitate forms. For any colour change, indicate both the initial and final colour, as well as the stage in which the change occurs if more than one reagents are added. If precipitate forms, state the colour of precipitate and whether it is soluble in excess of the reagent added, and if it is soluble state the colour of the solution formed. If you see any bubbles formed, it means that gas is released, and you should carry out gas tests to determine what the gas is. Only gas tests in the Qualitative Analysis Notes at the last page of question paper should be carried out. The gas can be any one of the 6 gases, but based on the type of reagents added and your experience in doing Chemistry practical work, you may be able to predict the type of gas released and thus choose the appropriate gas test to be carried out (For example, if a metal is added to an unknown solution and gas is released, it is likely that the solution is an acid and thus hydrogen gas is released, so you should carry out the gas test for hydrogen). State that effervescence occurs and state the observations of the gas test which is positive and the type of gas released. When determining the type of an unknown chemical, it should be based on your observations and refer to the Qualitative Analysis Notes at the last page of question paper.
- For any questions involving calculation, the number of significant figures of your answer should be equal to or one more than the number of significant figures of the raw value used in the calculation with the least number of significant figures. You should show all workings and do not skip any important steps. You must also write the correct unit for the final answer if it is not provided. You are not allowed to write extra solutions or answers. If you do so and any of the answers or solutions is wrong, marks will be deducted. For a calculation question which requires you to use your answer from the previous question, even if your answer for the previous question is wrong and you use it for this question causing your answer for this question to be wrong, usually you will still get full marks for this question as long as your calculation for this question is correct. This is known as 'error carried forward'.
- For questions that require explanation or description, your answer must be very detailed. You are advised to answer in complete sentences so that your answer can be easily understood. The number of marks allocated for the question usually shows the number of points needed in your answer. 1 mark is given for each correct point. Do not miss out any important points in your answer. You are allowed to write extra points in your answer, but you must be careful not to write any points with wrong facts. Marks will only be given for the correct points. For points that are irrelevant but does not contain wrong facts, no mark will be given or deducted. However, for points that contain wrong facts, marks may be deducted.
- For questions that do not require explanation or description, write the answer straight away. You need not answer in complete sentences. The number of marks allocated for the question usually shows the number of answers needed. If the question states the number of answers you have to write, then you are not allowed to write extra answers. If you do so, marks may not be given for the extra answers, and marks may be deducted if any of them is wrong. If the question does not state the number of answers you have to write, you are allowed to write extra answers, but you must be careful not to write any answer with wrong facts. Marks will only be given for the correct answers. For answers that are irrelevant but does not contain wrong facts, no mark will be given or deducted. However, for answers that contain wrong facts, marks may be deducted.
- When drawing diagrams, make sure that all important details are included in the diagram you draw. You have to label correctly all parts in the diagram. Your diagram should be clear and neat.
- For all questions, you should use the correct experimental and Chemistry terms in your answer. Do not replace them with other terms that are inappropriate, even if their meaning are the same. You should spell all experimental and Chemistry terms correctly. If you can't do so, try to spell it in such a way where it sounds the same as the actual term when read out. Marks are usually not deducted for spelling errors in experimental and Chemistry terms as long as it still sounds the same and that it is not easily confused with other terms. If you spell other terms wrongly or if you make grammatical errors in your answer, marks will not be deducted for as long as the examiner can understand what you are writing. You are allowed to use suitable short forms in your answer, such as formula for chemical substances and symbols for units of physical quantities.

5. Paper 5
- When answering, read the question and all information given carefully. Make sure that you understand the experiment given and know what the question is asking for. Answer the questions based on the experiment and its observations and results. You may need to apply your Chemistry experimental skills to answer some questions. Certain questions may require your knowledge and understanding in Chemistry to answer them. You may also need to give your own opinions. For all questions, your answer must be specific and not too general. Give the most suitable answer according to the question.
- You should use the correct Chemistry and experimental terms in your answer. Do not replace them with other terms that are inappropriate, even if their meaning are the same. You should spell all Chemistry and experimental terms correctly. If you can't do so, try to spell it in such a way where it sounds the same as the actual term when read out. Marks are usually not deducted for spelling errors in Chemistry and experimental terms as long as it still sounds the same and that it is not easily confused with other terms. If you spell other terms wrongly or if you make grammatical errors in your answer, marks will not be deducted for as long as the examiner can understand what you are writing. You are allowed to use suitable short forms in your answer, such as formula for chemical substances and symbols for units of physical quantities.
- It is not compulsory to answer in continuous writing form. You are allowed to answer in table form, point form or other suitable forms. In suitable cases, you can also use diagrams, equations or graphs in your answer.
- For any questions involving calculation, the number of significant figures of your answer should be equal to or one more than the number of significant figures of the raw value used in the calculation with the least number of significant figures. If you are in doubt, give your answer to 3 significant figures. You should show all workings and do not skip any important steps. You must also write the correct unit for the final answer if it is not provided. You are not allowed to write extra solutions or answers. If you do so and any of the answers or solutions is wrong, marks will be deducted. For a calculation question which requires you to use your answer from the previous question, even if your answer for the previous question is wrong and you use it for this question causing your answer for this question to be wrong, usually you will still get full marks for this question as long as your calculation for this question is correct. This is known as 'error carried forward'.
- For questions that require explanation or description, your answer must be very detailed. You are advised to answer in complete sentences so that your answer can be easily understood. The number of marks allocated for the question usually shows the number of points needed in your answer. 1 mark is given for each correct point. Do not miss out any important points in your answer. You are allowed to write extra points in your answer, but you must be careful not to write any points with wrong facts. Marks will only be given for the correct points. For points that are irrelevant but does not contain wrong facts, no mark will be given or deducted. However, for points that contain wrong facts, marks may be deducted.
- For questions that do not require explanation or description, write the answer straight away. You need not answer in complete sentences. The number of marks allocated for the question usually shows the number of answers needed. If the question states the number of answers you have to write, then you are not allowed to write extra answers. If you do so, marks may not be given for the extra answers, and marks may be deducted if any of them is wrong. If the question does not state the number of answers you have to write, you are allowed to write extra answers, but you must be careful not to write any answer with wrong facts. Marks will only be given for the correct answers. For answers that are irrelevant but does not contain wrong facts, no mark will be given or deducted. However, for answers that contain wrong facts, marks may be deducted.
- When drawing diagrams, make sure that all important details are included in the diagram you draw. You have to label correctly all parts in the diagram. Your diagram should be clear and neat.
- When plotting graph, draw both the horizontal and vertical axis on the graph paper correctly. Label both axis correctly and state the unit (if any). Use a suitable scale for both axis and do not use any odd scales such as 3:10. Both the x-axis and y-axis need not start from 0 (unless otherwise stated by the question). The scales should be chosen such that the points plotted on graph cover at least half of the graph paper. Plot all points on the graph accurately. The points should be accurate to half a small square. For all the points, their diameter should not be larger than half a small square. Then, draw the correct straight line or curve. When drawing the straight line or curve, it should pass through as many points on the graph as possible, all the points should be close to it and the number of points above and below the line or curve should be almost equal. However, usually one or more points on the graph are anomalous, which should be ignored when drawing the straight line or curve. The line or curve should not be deviated to accommodate them.
- For the question which asks you to suggest the reason for the anomalous points on the graph, common reasons are that a particular measurement is done before or after the moment it should be done, the actual value of a quantity is higher or lower than the measured value, incomplete oxidation/reduction, incomplete decomposition, loss of water/chemical, a compound has decomposed or other similar reasons.


Tips for other CIE AS and A Level subjects can be found here:

http://daniellimjj.blogspot.com/2014/09/complete-tips-for-cie-as-and-level.html

Saturday, 6 September 2014

Tips for CIE AS and A Level Physics

I got 4A for my AS Level in October 2013 and 4A* for my A Level in May 2014. One of the 4 subjects I took was Physics. My percentage uniform mark for Physics was 93% in AS Level and 95% in A Level. Do you want to know how to score in AS and A Level for Physics? Here, I am posting the complete tips for AS and A Level Physics. These tips are intended for students who are sitting for AS or A Level in October 2014, May 2015 or October 2015.

Tips for other CIE AS and A Level subjects can be found here:
http://daniellimjj.blogspot.com/2014/09/complete-tips-for-cie-as-and-level.html


1. Studying tips
- When your teacher is teaching in class, pay attention to what your teacher says. Make sure you understand everything taught by your teacher. If you do not understand anything, ask your teacher or friends.
- You need notes or reference books that are complete. As far as I know, no reference books in the market is complete. Instead, I recommend you to use my notes. You can download my notes here:
http://daniellimjj.blogspot.com/2014/06/full-notes-for-cambridge-international.html . However, if you know of any reference book that is complete, you may use it.
- When studying a chapter, read through all the explanations in my notes or in the reference book sentence by sentence. Make sure that you truly understand each sentence before moving on to the next sentence. You also need to know and understand all formulas. Certain topics may require understanding of earlier topics, so make sure you understand those topics. You should also try to relate them to what your teacher had taught in college or school.
- You should be actively involved in all experiments carried out in college or school because this can help improve your practical skills which are essential for Paper 3 and Paper 5.
- Then, you have to remember everything that you understood. You can memorise the sentences in my notes or in the reference book, or you can also create your own sentences that have the same meaning and memorise them. If you create your own sentences, make sure that you do not change the original meaning, do not leave out any important points and do not change the important keywords and scientific terms. However, do not just memorise without understanding. Once you have understood, it will be quite easy to remember and you will be unlikely to forget any of the points.
- For certain facts, there may be no explanation for them so it is not possible to understand them. In that case, you have to remember and memorise those facts.
- For the calculations, you need to know how to apply what you have learnt and use the correct formula to solve the questions. Go through all the example questions in my notes or in the reference book. Make sure that you understand how every question is solved.
- You have to regularly revise every topics again and again. When revising, go through all the explanation, facts and examples for calculation questions in my notes or in the reference book. Make sure that you do not forget anything that you have understood previously. Regular and repeated revision will help you to remember all the explanation and facts for a long time.
- When you have understood all topics, you have to do past year A Level questions. They are available on
http://papers.xtremepapers.com/CIE/Cambridge%20International%20A%20and%20AS%20Level/ . After doing the questions, refer to the mark scheme and do self marking. The mark schemes can be found on the same website as the past year questions.
- You should understand how the mark schemes are used. In the mark schemes for Physics, there are 4 types of marks, which are M, C, A and B. The A marks are always dependent on the M marks, which means that A marks can only be scored if the M marks are also scored. If a question does not have M mark, then the A mark can be scored on its own. C marks are automatically scored if the subsequent M or A mark is scored, even if the points for the C marks are not written down, but if the subsequent M or A mark is not scored, then the points for the C marks must be written down in order for the C marks to be scored. On the other hand, B marks are independent of any other marks, which means that they can be scored without other marks also being scored. If any Physics term is underlined or highlighted, it means that the exact term must be used in the answer and no other term is acceptable even if the meaning is the same, but grammatical variants of the term is accepted. If any non-Physics term is underlined or highlighted, it means that either the exact term or other terms with the same meaning must be used in the answer. If any words are placed in brackets, it means that the words need not be present in the answer for the mark to be scored. In the mark schemes, A means accept, I means ignore while R means reject.
- When doing revision before exam, you should first go through the subtopics that you think is more difficult or that you may have forgotten. Then, go through other topics as well if possible.
- To prepare for Physics Paper 3 and Paper 5, you should go through all the past year questions and the mark schemes. Find out how every question is marked and which points need to be included in the answers. The pattern of questions set is similar for every year and you should familiarise yourself with the pattern. Usually, the same type of questions will have similar mark scheme, so this can help you when answering exam questions. You should remember the answers for questions that are common.
- For Physics Paper 3, I also suggest that you memorise my list of 20 common answers (see below) for the limitations and suggestions question which appears in the last part of Question 2. My list is based on the mark schemes for past year questions. Usually 3 of the 4 answers required can be found in my list, and the 1st answer in my list can be used for all experiments. Sometimes, only 2 of the 4 answers required can be found in my list, and sometimes, all the 4 answers required can be found in my list. Note that for the parts of the answers in my list that are placed in brackets, it means that you have to write those parts based on the context of the experiment.

The List of Common Answers for the Limitations and Improvements Question of Paper 3 Question 2:

1. Two/three readings are not enough to make a valid conclusion
- Take more readings and plot a graph
Note: This answer can be used for all experiments

2. The value of (a physical quantity) is small so the percentage uncertainty of (the quantity) is large
- (The way to make the value of the quantity larger)

3. The movement/oscillation of (something) is affected by wind movement
- Use a wind shield when carrying out the experiment

4. Difficult to determine the start and end of oscillation/movement of (something) because it moves too fast
- Use a video camera with slow motion feature and timer to video the experiment with scale, then view the video playback frame by frame.

5. Difficult to release (something) without applying a force
- Use a mechanical hand to release the (thing)

6. Difficult to shape the plasticine into the shape of (something)
- Use a mould to shape the plasticine

7. Heat loss through the sides and bottom of beaker/container
- Use polystyrene container or insulate the beaker/container
Note: This answer should be used for experiments involving the temperature of liquid.

8. The (measuring instrument) is not precise enough
- Use another (instrument) with greater sensitivity and precision

9. The length/diameter/thickness of (something) is not uniform
- Measure the length around/along the (thing) and calculate the mean

10. Difficult to measure (something) due to … (must state specific reason based on experiment)
- (Suggest a better way to measure it)

11. Parallax error when measuring (something)
- (Suggest a better way to measure it, such as use mirror scale)
Note: This answer should only be used if the measurement is difficult to make and parallax error is very likely to occur.

12. (Something) moves
- (Way to keep it in the original position)

13. Oscillation does not occur in one plane only
Note: No possible improvement for this limitation. You should write the improvement for any other limitation in your answer.

14. Difficult to maintain (something) at a particular position / maintain ruler vertical
- Use a clamp

15. Difficult to zero the newton-meter when used horizontally
Note: No possible improvement for this limitation. You should write the improvement for any other limitation in your answer.

16. Friction at pulley
- Apply oil to lubricate the pulley

17. Resistance of contacts
- Clean the contacts
Note: This answer should be used for electric experiments.

18. Difficult to determine when (something) reach the maximum height because it remains there for too short a time
19. Difficult to take the reading of newton-meter immediately when (something) starts to move
because it moves suddenly
20. Difficult to start or stop the stopwatch immediately when (something) passes through (somewhere)
- Use a video camera with slow motion feature and (the measuring device) to video the experiment with scale, then view the video playback frame by frame.
Note: The same improvement can be used for limitations 18, 19 and 20.

2. Paper 1
- Read the question and all the options carefully. Write any rough workings on the question paper if you need to. Cancel off the options that you consider as definitely wrong. Then, choose the most suitable answer among the options.

3. Paper 2 and Paper 4
- When answering, read the question and all information given carefully. Make sure that you know what the question is asking for. Answer the questions based on your knowledge and understanding on the relevant topic in Physics. Certain questions may test you on more than one topics. For some questions, you may have to apply what you have learnt in Physics in order to answer them. You have to think carefully and relate the question to what you have learnt. You may also be asked to give your own opinions.
- When writing your answer, you can use the same or similar words or sentences as those in my notes or in the reference books if possible. However, sometimes you may need to make some changes in order to suit the question. You can also answer in your own sentences that have the same meaning. If the question asks on something that is not in my notes and the reference books (the question requires you to apply what you have learnt in Physics or give your own opinion), then you have to answer in your own sentences. For all questions, your answer must be specific and not too general. Give the most suitable answer according to the question.
- You should use the correct Physics terms in your answer. Do not replace them with other terms that are inappropriate, even if their meaning are the same. You should spell all Physics terms correctly. If you can't do so, try to spell it in such a way where it sounds the same as the actual term when read out. Marks are usually not deducted for spelling errors in Physics terms as long as it still sounds the same and that it is not easily confused with other terms. If you spell a non-Physics term wrongly or if you make grammatical errors in your answer, marks will not be deducted for as long as the examiner can understand what you are writing. You are allowed to use suitable short forms in your answer, especially for representing physical quantities or their units.
- It is not compulsory to answer in continuous writing form. You are allowed to answer in table form, point form or other suitable forms. In suitable cases, you can also use diagrams, equations or graphs in your answer.
- When answering questions on calculation, you should show all workings. You should not skip any important steps. You must also write the correct unit for the final answer if it is not provided. You are advised to write down the formula used to solve the question, even though it is not compulsory to do so. The number of marks allocated for the question usually shows the amount of working needed. 1 mark will be given for each important step and the final answer. In some cases, if your final answer is correct, full marks will be given and the workings will not be marked. In other cases, marks can only be given for the final answer if the marks for working are scored, where correct answer without working scores 0 mark. Whichever case, if your final answer is wrong but some of your working is correct, you may still be given some marks. You are not allowed to write extra solutions or answers. If you do so and any of the answers or solutions is wrong, marks will be deducted. When copying figures from the question or from your answer for the previous part of the question, be careful not to copy wrongly. For a calculation question which requires you to use your answer from the previous question, even if your answer for the previous question is wrong and you use it for this question causing your answer for this question to be wrong, usually you will still get full marks for this question as long as your calculation for this question is correct. This is known as 'error carried forward'. For questions on 'show', 'prove', 'derive' or similar, usually marks are only given for the workings, not the answer, so it is important that you show complete workings, and explain your workings if necessary.
- Usually, you should give the final answer to 3 significant figures. Do not write your final answer as a fraction or in surd form. However, if the question asks you to give your answer to a specific number of significant figures, then you must follow the instruction, or if the question states that you must give your answer to a suitable number of significant figures, then the number of significant figures of your answer should be equal to the number of significant figures of the raw value used in the calculation with the least number of significant figures.
- When answering questions which requires you to give an answer as well as an explanation to your answer, such as questions that say 'State and explain', 'Suggest and explain' or something similar, it is very important that you give a complete and clear explanation. Marks can only be given for the answer if the marks for explanation are scored. Therefore, correct answer without satisfactory explanation usually scores 0 mark. On the other hand, if your answer is wrong but some of your explanation is correct, you may still be given some marks. In other words, 'explain' is more important than 'state' or 'suggest'.
-  For questions that require explanation or description, your answer must be very detailed. You are advised to answer in complete sentences so that your answer can be easily understood. The number of marks allocated for the question usually shows the number of points needed in your answer. 1 mark is given for each correct point. Some of the marks (A marks) may be dependent on other marks (M marks), which means that they can only be scored if the other marks are also scored. Do not miss out any important points in your answer. You are allowed to write extra points in your answer, but you must be careful not to write any points with wrong facts. Marks will only be given for the correct points. For points that are irrelevant but does not contain wrong facts, no mark will be given or deducted. However, for points that contain wrong facts, marks may be deducted.
- For questions that do not require explanation or description, write the answer straight away. You need not answer in complete sentences. The number of marks allocated for the question usually shows the number of answers needed. If the question states the number of answers you have to write, then you are not allowed to write extra answers. If you do so, marks may not be given for the extra answers, and marks may be deducted if any of them is wrong. If the question does not state the number of answers you have to write, you are allowed to write extra answers, but you must be careful not to write any answer with wrong facts. Marks will only be given for the correct answers. For answers that are irrelevant but does not contain wrong facts, no mark will be given or deducted. However, for answers that contain wrong facts, marks may be deducted.
- When drawing diagrams, make sure that all important details are included in the diagram you draw. You have to label correctly all parts in the diagram. Your diagram should be clear and neat.

4. Paper 3
- During the test, read the question and all information given carefully. Make sure that you understand the experiment given. Certain parts of the question require you to record the readings from the experiment in a table. You should draw the tables before carrying out the experiment so that you can record your readings in the table straight away during the experiment. Then, carry out the experiment by following the steps given in the question exactly. You need to apply your Physics practical skills when carrying out the experiment.
- Certain questions may require your knowledge and understanding in Physics to answer them. You may also need to give your own opinions. Your answer must be specific and not too general. Give the most suitable answer according to the question.
- When recording readings from an measuring instrument (except metre rule, vernier calipers and micrometre screw gauge), the number of decimal places used should be equal to half of the smallest division of scale of the instrument (For example, if the instrument's smallest division of scale is 0.1, you should record the reading to the nearest 0.05, which is 2 decimal places.) For digital instruments (except digital stopwatch), the number of decimal places used should be the same as that shown on the display. The reading should be recorded to the nearest 0.1cm for metre rule, 0.01cm for vernier calipers, 0.01mm for micrometer screw gauge and 0.1s for stopwatch (both analogue and digital). In all cases, do not give more or less number of decimal places. You must also write the correct units.
- In most cases, you should take each reading twice, then calculate and record the mean of the 2 readings. Ensure that you show in your answer both readings and the calculation of their mean. However, for the part in Question 1 which requires you to record readings in a table, questions that carry only 1 mark and questions which states that repeated readings are not required, you only need to take each reading once and record it straight away.
- When plotting graph, draw both the horizontal and vertical axis on the graph paper correctly. Label both axis correctly and state the unit (if any). Use a suitable scale for both axis and do not use any odd scales such as 3:10. Both the x-axis and y-axis need not start from 0. The scales should be chosen such that the points plotted on graph cover at least half of the graph paper. The markings on the scales should not be more than 3 large squares apart. Plot all points on the graph accurately. The points should be accurate to half a small square. For all the points, their diameter should not be larger than half a small square. Then, draw the correct straight line or curve. When drawing the straight line or curve, it should pass through all points on the graph if possible. If this is not possible, the line or curve should pass through as many points on the graph as possible, all the points should be close to it and the number of points above and below the line or curve should be almost equal.
- When determining the gradient of the line of graph, choose 2 points on the line and draw a triangle. The distance between the 2 points chosen should be at least half the length of the line. When determining the y-intercept of the line of graph, if the x-axis starts from 0, you can read it off directly from the y-axis of graph, or if the x-axis does not start from 0, you should choose a point on the line, preferably one of the points that you used to calculate its gradient, and substitute its x and y values as well as the gradient into the equation y=mx+c to determine the value of c which is the y-intercept.
- For any questions involving calculation, the number of significant figures of your answer should be equal to or one more than the number of significant figures of the raw value used in the calculation with the least number of significant figures. You should show all workings and do not skip any important steps. You must also write the correct unit for the final answer if it is not provided. You are not allowed to write extra solutions or answers. If you do so and any of the answers or solutions is wrong, marks will be deducted. For a calculation question which requires you to use your answer from the previous question, even if your answer for the previous question is wrong and you use it for this question causing your answer for this question to be wrong, usually you will still get full marks for this question as long as your calculation for this question is correct. This is known as 'error carried forward'.
- For the part of Question 2 which asks you to estimate the percentage uncertainty in a particular value, in most cases the absolute uncertainty used to calculate the percentage uncertainty should be equal to twice the smallest division of scale of the instrument used to measure the value (For both analogue and digital stopwatch, the absolute uncertainty used should be 0.2s). This is because the measurement for this part is often difficult to be done accurately.
- For the part of Question 2 which asks you whether your results support the suggested relationship between 2 variables, you have to calculate the percentage difference between 2 values of a constant which is obtained in previous part of the question. The suggested relationship is supported if the percentage difference is 5% or less and not supported if the percentage difference is more than 5%.
- For the last part of Question 2 which is about limitations and improvements, I would suggest that you use answers from my list of 20 common answers (see above) that you memorised. The 1st answer in my list can be used for all experiments, so you should always use it. You should also choose other answers from my list which are relevant to the experiment. You may have to give 1 or sometimes 2 other relevant answers that are not in my list since usually not all the 4 answers required can be found in my list. You are not allowed to write more than 4 answers. If you do so, marks may not be given for the extra answers, and marks may be deducted if any of them is wrong.
- For all questions, you should use the correct experimental and Physics terms in your answer. Do not replace them with other terms that are inappropriate, even if their meaning are the same. You should spell all experimental and Physics terms correctly. If you can't do so, try to spell it in such a way where it sounds the same as the actual term when read out. Marks are usually not deducted for spelling errors in experimental and Physics terms as long as it still sounds the same and that it is not easily confused with other terms. If you spell other terms wrongly or if you make grammatical errors in your answer, marks will not be deducted for as long as the examiner can understand what you are writing. You are allowed to use suitable short forms in your answer, especially for representing physical quantities or their units.

5. Paper 5 Question 1 (Planning Experiment)
- When answering, read the question given carefully. You have to design a suitable experiment based on the question, either to test whether the suggested relationship between 2 variables is valid or to determine the value of a constant. Your answer must include independent variable, dependent variable, variables to be kept constant, diagram of set-up apparatus, procedure, data analysis, safety precautions and additional details.
- For the independent variable and dependent variable, they can be obtained easily from the question itself and you should give one of each. For the variables to be kept constant, there is often more than one and you should give all of them that you can think of. Note that the term 'kept constant' or 'keep constant' must be used in your answer and no other terms are acceptable. You need not answer in complete sentences.
- For the diagram of set-up apparatus, show all the apparatus and material used in the experiment and label them correctly. If a diagram is provided by the question, you can use the same diagram, but it is usually not complete and you have to add other apparatus or materials to it.
- When writing the procedure, you must include the steps to measure the manipulated variable, responding variable and every variable to be kept constant. For each measurement, you should state the method and apparatus used. For some variables, you may have to measure other quantities in order to calculate them. You are advised to answer in complete sentences so that your answer can be easily understood. You should also include other steps required to set up the apparatus if you did not show them in the diagram.
- For the analysis of data, you should explain how a suitable graph should be plotted that enables you to test whether the suggested relationship between the 2 variables is valid or to determine the value of the constant. Sometimes, the graph may be a log-log graph or ln-ln graph. You should also show a sketch of the graph. Then, explain how to determine whether the suggested relationship is valid or to determine the value of the constant based on the graph. This often involves the gradient, y-intercept and rearranging of equation.
- For the safety precaution, you should state at least 2 potential safety hazards when carrying out the experiment and the ways to avoid each of them.
- For the additional details, 4 marks will be given and examples of them are how variables are kept constant, calibration of the measuring instruments and additional steps to improve the accuracy and reliability. You may have already stated some of them in other parts of your answer and it is not compulsory to write them again in this part. In this section, you should state the additional details that are not stated in other parts of your answer.
- For all parts of the question, you are allowed to write extra points in your answer, but you must be careful not to write any points with wrong facts. Marks will only be given for the correct points. For points that are irrelevant but does not contain wrong facts, no mark will be given or deducted. However, for points that contain wrong facts, marks may be deducted.
- You should use the correct experimental and Physics terms in your answer. Do not replace them with other terms that are inappropriate, even if their meaning are the same. You should spell all experimental and Physics terms correctly. If you can't do so, try to spell it in such a way where it sounds the same as the actual term when read out. Marks are usually not deducted for spelling errors in experimental and Physics terms as long as it still sounds the same and that it is not easily confused with other terms. If you spell other terms wrongly or if you make grammatical errors in your answer, marks will not be deducted for as long as the examiner can understand what you are writing. You are allowed to use suitable short forms in your answer, especially for representing physical quantities or their units.

6. Paper 5 Question 2 (Analysis, Conclusions and Evaluation)
- When answering, read the question and all information given carefully. Make sure that you understand the experiment given and know what the question is asking for. Answer the questions based on the experiment and its observations and results. You may need to apply your Physics experimental skills to answer some questions. Certain questions may require your knowledge and understanding in Physics to answer them.
- For the graph, plot all points on the graph accurately. The points should be accurate to half a small square. Then, draw the error bars based on the uncertainties of the values given in the question. After that, draw line of best fit. The line should pass through as many points on the graph as possible, all the points should be close to it and the number of points above and below the line should be almost equal. Next, draw the worst acceptable line. It should be either the steepest possible line which passes from the top of top error bar to the bottom of bottom error bar or or the shallowest possible line which passes from the bottom of top error bar to top of bottom error bar. The line must also pass through all error bars.
- When determining the gradient of line of best fit, choose 2 points on the line and draw a triangle. The distance between the 2 points chosen should be at least half the length of the line. For the uncertainty in gradient, you should also determine the gradient of worst acceptable line using the same method. The uncertainty in gradient is equal to the difference between the 2 gradients.
- When determining the y-intercept of line of best fit, usually you cannot read it off directly from the y-axis of graph since the x-axis does not start from 0. Instead, you should choose a point on the line, preferably one of the points that you used to calculate its gradient, and substitute its x and y values as well as the gradient into the equation y=mx+c to determine the value of c which is the y-intercept. For the uncertainty in y-intercept, you should also determine the y-intercept of worst acceptable line using the same method. The uncertainty in y-intercept is equal to the difference between the 2 y-intercepts.
- When calculating the uncertainty in a calculated value, use your knowledge in uncertainties that you learnt in Chapter 2 for AS Level. However, if the calculation is too complicating or if it involves logarithms, there is an alternative method. For this method, you have to determine both the maximum value and minimum value of the calculated value by using the maximum values and/or minimum values of the raw values used in the calculation of the calculated value based on their uncertainties. You have to be very careful to ensure that the maximum value and minimum value you determined are correct. The absolute uncertainty is equal to half of the difference between the maximum and minimum value.
- For any questions involving calculation, the number of significant figures of your answer should be equal to or one more than the number of significant figures of the raw value used in the calculation with the least number of significant figures. For absolute uncertainties, the number of decimal places should be equal to the number of decimal places of the value. You should show all workings and do not skip any important steps. You must also write the correct unit for the final answer if it is not provided. You are not allowed to write extra solutions or answers. If you do so and any of the answers or solutions is wrong, marks will be deducted. For a calculation question which requires you to use your answer from the previous question, even if your answer for the previous question is wrong and you use it for this question causing your answer for this question to be wrong, usually you will still get full marks for this question as long as your calculation for this question is correct. This is known as 'error carried forward'.


Tips for other CIE AS and A Level subjects can be found here:
http://daniellimjj.blogspot.com/2014/09/complete-tips-for-cie-as-and-level.html

Friday, 5 September 2014

Tips for CIE AS and A Level Mathematics

I got 4A for my AS Level in October 2013 and 4A* for my A Level in May 2014. One of the 4 subjects I took was Mathematics. My percentage uniform mark for Mathematics was 96% in AS Level and 94% in A Level. Do you want to know how to score in AS and A Level for Mathematics? Here, I am posting the complete tips for AS and A Level Mathematics. These tips are intended for students who are sitting for AS or A Level in October 2014, May 2015 or October 2015.

Tips for other CIE AS and A Level subjects can be found here:
http://daniellimjj.blogspot.com/2014/09/complete-tips-for-cie-as-and-level.html


1. Studying tips
- When your teacher is teaching in class, pay attention to what your teacher says. Make sure you understand everything taught by your teacher. If you do not understand anything, ask your teacher or friends.
- You need reference books that are complete. I recommend you to use the following reference book for each paper:
Paper 1: Pure Mathematics 1 for Cambridge International A Level, by Bostock, L, Chandler, S and Jennings, T (Nelson Thornes, UK)
Paper 2 & Paper 3: Pure Mathematics 2 and 3 for Cambridge International A Level, by Bostock, L, Chandler, S and Jennings, T (Nelson Thornes, UK)
Paper 4: Mechanics 1 for Cambridge International A Level, by Bostock, L, Chandler, S and Lee, D A (Nelson Thornes, UK)
Paper 5: Mechanics 2 for Cambridge International A Level, by Bostock, L, Chandler, S and Lee, D A (Nelson Thornes, UK)
Paper 6: Probability and Statistics 1 for Cambridge International A Level, by Chambers, J, Crawshaw, J and Balaam, P (Nelson Thornes, UK)
Paper 7: Probability and Statistics 2 for Cambridge International A Level, by Chambers, J, Crawshaw, J and Balaam, P (Nelson Thornes, UK)
- When studying a chapter for the first time, read through the notes in the reference book. Make sure that you understand the concept for that chapter and relate them to what your teacher had taught in school.
- You need to know how to apply what you have learnt to solve questions. Go through all the example questions in the reference book. Make sure that you understand how every question is solved.
- Then, you have to do a lot of exercises. You can start by doing questions in the reference books topic by topic. When you have understood all topics, proceed with doing past year A Level questions. They are available on
http://papers.xtremepapers.com/CIE/Cambridge%20International%20A%20and%20AS%20Level/ . After doing the questions, refer to the mark scheme and do self marking. The mark schemes can be found on the same website as the past year questions.
- You should understand how the mark schemes are used. In the mark schemes for Mathematics, there are 3 types of marks, which are M, A and B. The A marks are always dependent on the M marks before them, which means that A marks can only be scored if the M marks before them are also scored. On the other hand, B marks are independent of any other marks, which means that they can be scored without other marks also being scored.
- When doing revision before exam, you should go through the example questions for all chapters in the reference book. If you have forgotten the concept for any chapter, go through the notes in reference book for that chapter again. You should also do some past year questions.
- A Level Mathematics also requires knowledge gained from SPM, IGCSE or equivalent, although it does not test on them directly. Make sure that you do not forget them.

2. Answering tips for all papers (Paper 1 to 7)
- You must show all workings for every question. You should not skip any important steps. You do not need to write down the formula used to solve the question. The number of marks allocated for a question usually shows the amount of working needed. 1 mark will be given for each important step and the final answer. Marks can only be given for the final answer if the marks for working are scored. Therefore, correct answer without working usually scores 0 mark.
- On the other hand, if your final answer is wrong but some of your working is correct, you may still be given some marks. You are not allowed to write extra solutions or answers for any question. If you do so and any of the answers/solutions is wrong, marks will be deducted. When copying figures from the question or from your answer for the previous part of the question, be careful not to copy wrongly.
- For a part of question which requires you to use your answer from the previous part, even if your answer for the previous part is wrong and you use it for this part, causing your answer for this part to be wrong, you will still get the working marks (M marks) for this part as long as your calculation for this part is correct, but you will usually lose the answer marks (A marks) for this part.
- When answering, read the question and information given carefully. For questions involving diagrams, mark any important details on the diagram. For some questions without diagram, sometimes it may be helpful to draw a diagram so that you can illustrate the information given in the question. Apply what you have learnt in mathematics in order to solve the questions and get the answer. Use the correct concept or formula for every question. Certain formula are provided in the formula booklet, refer to them if necessary.
- If the question does not state that you must or you cannot use a particular method, then you can use any suitable method to solve the question. You can also use methods that are not learnt in the A Level syllabus, if you know them. If the question states that you must use a particular method, then you can only that method to solve the question. If the question states that cannot use a particular method, then you cannot that method to solve the question.
- If the final answer is a number with infinite decimal places, you should round up to at least 3 significant figures, unless if the question states that you have to give your answer to a specific number of significant figures. You can also write your final answer as a fraction or in surd form if possible. However, if the question states that you must express your answer as fraction, as decimal or in surd form, then you must follow the instruction. If a number with infinite decimal places is involved in between the workings, you should take at least 4 or 5 significant figures (3 significant figures is not sufficient) or the value stored in the calculator to ensure accuracy of the final answer. Otherwise, marks may be deducted if the final answer is less accurate.
- For questions involving Pi, you should use the value of Pi from the calculator, unless if the question asks you to use Pi = 22/7 or Pi = 3.142 . You must also follow all other special instructions given in the question. After you have answered all questions, you should recheck your answers for mistakes. Leave at least 15 minutes to recheck your answers if possible. When rechecking, use a different method to solve the question or directly use the calculator if possible.


Tips for other CIE AS and A Level subjects can be found here:
http://daniellimjj.blogspot.com/2014/09/complete-tips-for-cie-as-and-level.html