gz_HSCTUTOR
Member
- Joined
- Dec 2, 2012
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- Male
- HSC
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A General Overview
1. Always refer to the notes from the marking centre and the marking guidelines from previous HSC exams
- This is where you get information on band 6 answers
- By constantly referring to these guidelines, you will become used to what is expected of you and when answering questions getting a band 6 will become almost natural
2. Make sure you read the question & the verb
- Explain questions MUST show cause and effect (TALK ABOUT PHYSICS PRINCIPLES e.g. Motor effect or Lenz's law)
- Assess questions MUST have a judgement in the answer and ensure that it is clear (It is ok to say: My judgement is...)
3. The HSC Physics Syllabus is your best friend!
- If you follow the syllabus there will never be any nasty surprises in your exams!
4. If given the opportunity ALWAYS put in a physics formula/equation in your answer
- Even if you get a calculation question wrong, you will be rewarded 1 mark just for the formula
- During long response questions a formula will ALWAYS help with your explanations
5. Long response questions (questions worth 4 marks or more) can be answered in table or point form
- Marking scheme always say; "logically & coherently written"
6. Read the question carefully! Using an example from the 2012 HSC Physics - Qu 22 I will show you what I mean:
(I can't attach an image here so you can visit the Board of Studies website to gain access to the paper or you can visit my blog)
- In a), what most students will do is they will usually write a memorised answer and won't really take notice of the diagram. Most students won't explain Lenz's law properly and will simply say when there is change in flux a current is induced or they will only talk about short circuits.
However, to get the full marks students need to say:
Lenz's law states when there is a change in flux there is an induced emf which will lead to an induced current in a closed circuit (Change in flux -> Induced emf -> Induced current). (1st mark)
Therefore, in the above diagram as the magnet passes through the magnetic field in the coil, there is a change in magnetic flux. Due to the decreasing magnetic flux as the coil is moved away, an emf is then induced. Due to the coil terminals being short-circuited, the emf will result in an induced current to flow. (2nd mark)
- In b), the key words here are 'explain' and 'changes'. Remember explain always means use cause and effect, which also means use PHYSICS PRINCIPLES. The word 'changes', means that the answer requires multiple answers. Many students will start talking about changes in mass but they forget mass is constant and the balance is measuring a FORCE (PHYSICS PRINCIPLE).
Therefore, a suitable sample answer would be:
As the coils are lifted, the readings on the balance will decrease and then return to 42.42g. The change in flux which causes the induced current produces a magnetic field that maintains flux throughout the solenoid (1st mark). On the bottom of the coil there is a south pole which causes a forces of attraction towards to the magnet ( 2nd mark). As the magnet is attracted towards the south pole, it causes the reading on the balance to decrease (3rd mark). However, as the coil is moved further away, the force of attraction between the magnetic and coil disappears as the force of attraction is not greater then the weight force of the magnet. This results in the reading of the balance to return to 42.42g. (4th mark)
1. Always refer to the notes from the marking centre and the marking guidelines from previous HSC exams
- This is where you get information on band 6 answers
- By constantly referring to these guidelines, you will become used to what is expected of you and when answering questions getting a band 6 will become almost natural
2. Make sure you read the question & the verb
- Explain questions MUST show cause and effect (TALK ABOUT PHYSICS PRINCIPLES e.g. Motor effect or Lenz's law)
- Assess questions MUST have a judgement in the answer and ensure that it is clear (It is ok to say: My judgement is...)
3. The HSC Physics Syllabus is your best friend!
- If you follow the syllabus there will never be any nasty surprises in your exams!
4. If given the opportunity ALWAYS put in a physics formula/equation in your answer
- Even if you get a calculation question wrong, you will be rewarded 1 mark just for the formula
- During long response questions a formula will ALWAYS help with your explanations
5. Long response questions (questions worth 4 marks or more) can be answered in table or point form
- Marking scheme always say; "logically & coherently written"
6. Read the question carefully! Using an example from the 2012 HSC Physics - Qu 22 I will show you what I mean:
(I can't attach an image here so you can visit the Board of Studies website to gain access to the paper or you can visit my blog)
- In a), what most students will do is they will usually write a memorised answer and won't really take notice of the diagram. Most students won't explain Lenz's law properly and will simply say when there is change in flux a current is induced or they will only talk about short circuits.
However, to get the full marks students need to say:
Lenz's law states when there is a change in flux there is an induced emf which will lead to an induced current in a closed circuit (Change in flux -> Induced emf -> Induced current). (1st mark)
Therefore, in the above diagram as the magnet passes through the magnetic field in the coil, there is a change in magnetic flux. Due to the decreasing magnetic flux as the coil is moved away, an emf is then induced. Due to the coil terminals being short-circuited, the emf will result in an induced current to flow. (2nd mark)
- In b), the key words here are 'explain' and 'changes'. Remember explain always means use cause and effect, which also means use PHYSICS PRINCIPLES. The word 'changes', means that the answer requires multiple answers. Many students will start talking about changes in mass but they forget mass is constant and the balance is measuring a FORCE (PHYSICS PRINCIPLE).
Therefore, a suitable sample answer would be:
As the coils are lifted, the readings on the balance will decrease and then return to 42.42g. The change in flux which causes the induced current produces a magnetic field that maintains flux throughout the solenoid (1st mark). On the bottom of the coil there is a south pole which causes a forces of attraction towards to the magnet ( 2nd mark). As the magnet is attracted towards the south pole, it causes the reading on the balance to decrease (3rd mark). However, as the coil is moved further away, the force of attraction between the magnetic and coil disappears as the force of attraction is not greater then the weight force of the magnet. This results in the reading of the balance to return to 42.42g. (4th mark)
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