1. Andrew R. Hansen Ringwood Secondary College

2. Use black or blue pen as stipulated in instructions. (Q15) Show working for questions worth more than 1 mark, as per instructions. Do not rely on prepared statements from A3 sheet. Check for ridiculous answers.

3. the vector nature of momentum centripetal force energy conversion and conservation in springs more complex projectile motion apparent weightlessness explaining direction of induced current using Lenz’s law operation of transformers and how they work in a power transmission system understanding of series and parallel circuits explaining aspects of the photoelectric effect applying the concept of path difference in interference patterns explaining electron and X-ray diffraction patterns electron energy level diagrams and associated emissions and absorptions how the wave nature of matter can explain the electron energy levels

5. Students must understand the vector nature of momentum.

7. Students must understand forces in vertical circular motion.

9. Common errors involve breaking the flight up into multiple phases (launch to top, top to init height, final drop) which led to errors. Difficult for the assessors to follow.

11. Students must understand that there are three energy’s that need to be accounted for.

12. At x=0 there is no spring force and a=g (-10). At the mid point the spring force = the gravitational force and a=0. At the bottom the spring provides an upwards force giving a=10.

13. While many students were able to identify C, they were unable to explain why in a coherent way. Those that selected responses other than C gave supporting arguments that were not realistic. Springs make up 20% of the marks in motion and students need a more thorough understanding of the underlying Physics.

14. Yes. The astronauts experience apparent weightlessness as they are still in a gravitational field, and therefore have weight, but they experience no normal reaction force.

15. A number of students said “no they would not feel weightless” and then went on to explain that they would feel “apparently weightless”. There were also a number of students who believe that weightlessness (of any kind) can only exist in a region without gravity.

17. There were a number of poorly designed circuits, some suggesting that students had never studied electronics at all. The most problematic was the “short circuiting” by trying to create a circuit, as shown.

20. Students need to know which resistor is which in the voltage divider equation and how to use this formula. R’s are mixed up.

21. The amplifier is an inverting amplifier and the waveform demonstrates clipping which is where the output of the amplifier exceeds the maximum supply voltage. (or similar)

22. The most common error was to focus on the clipping and fail to comment on the inversion.

24. The most common errors were: omission of n. failure to convert cm to m incorrect value for t

25. Replace the commutator with slip rings. The slip rings maintain a constant connection with the loop. As the loop rotates an AC current will be generated in the loop which is then transmitted to the oscilloscope.

26. The most common error was to rely on stock answers from the A3 sheet regarding the difference between slip rings and a split ring commutator. Stock descriptions did not respond to the question being asked.

28. Over half the responses scored no marks. Most diagrams were nonsensical and showed that students had a poor understanding of electromagnetic induction.

29. The initial flux is down and increasing. Lenz’s Law states that the induced current will give rise to a change in flux that opposes the change that induced it. The induced flux will be up and increasing. The right hand grip rule shows a current from y-x in the loop will give an upwards flux. Therefore the current will flow from x to y through the voltmeter.

30. Marks awarded for this question varied. Most students were able to identify some of the required points but most were unable to provide a thorough response. Students should practice responding to these high scoring questions.

31. A real situation would be a power station supplying power to a town. For a constant power delivery, transformers can be used to increase the transmission voltage and decrease the transmission current. Since power loss = I 2 R, reducing the current will significantly reduce the power loss.

32. Marks awarded for this question varied. Most students were able to identify some of the required points but most were unable to provide a thorough response. The most commonly omitted point was the need to maintain the delivered power while varying the supply parameters. Students should practice responding to these high scoring questions.

33. Same gradient. Intercept at 7.5

34. The most common errors were the wrong gradient or an intercept of 10.

35. Electrons diffract when they interact with things like crystals or narrow slits. Diffraction is a wave phenomenon.

36. Many students refered to Young’s Double Slit experiment. Young experimented with light not electrons so the argument is not valid.

37. Electrons exhibit a wave behavior. Allowed orbits are where the circumference is a whole multiple of the electron wavelength and a standing wave can be formed. Different orbits have different whole multiples of the electron wavelength.

38. Students had trouble linking the concept of a standing wave to the integer multiple of the electron wavelength. Students seem to think that electrons follow a sinusoidal path around the nucleus.

40. Students who tried to draw a sinusoidal pattern on a strip of paper had trouble demonstrating the standing wave nature.

41. Andrew R. Hansen Ringwood Secondary College