Re: 2009 HSC Physics - How did you go?
Here is the MC section scanned:
2009 MC Physics.doc
My suggested answers:
I think a few may be wrong see what others say. Actually I am quite confident with them now
feel free to rebut them..
1. C - sling shot changes direction and increases the speed of probe
2. A - mathematical ac=V^2/r
3. D - as the work done is the difference from infinity to geo and infinity to higher orbit. A is another correct possibility but not the best answer ???? Also why didn't they say infinity and instead say a very large distance away... arghhhh!!!
4. D - best answer as the range is different therefore X-Ux and Y-Ux are different but the objects hit the ground simultaneously as they have no vertical velocity.
5. B - gravitational force = G M1 M2/r^2 so therefore between sun and moon during lunar eclipse moon is at its furthest from the sun, hence r increases F decreases.
6. A - C and D are incorrect. Increasing rotational speed decreases the time therefore with Faraday's law EMF = -Change in flux/ time time decreases EMF increases.
7. C - rotates in the same direction as the magnetic field- being dragged along.
8. C - essential is induction which is the process of magnetic interaction between two coils
9. A - Use FBI rule to oppose the velocity direction with thumb(force) of left hand and index finger into the page then third finger points to the right which is conventional current + charge movement. Therefore + moves to the right and therefore electron must be on the left where p is. reverse thumb rule for electron direction..Nice question.
10. B - Confirmed....... This one will catch a few students... Agreed that Germanium is less abundant (some students would have chosen the converse for C which has Silicon as more abundant) and YES the energy level for Silicon is much more larger than germanium hence at higher temp it still remains a relatively good semiconductor... what a crazy question.... seems whoever wrote this gave there students an assignment on the history of germanium vs silicon. NSW BOS show em the outcome from the syllabus this question is based upon... GEEZ......
11. B - toque is a maximum at start and force is a maximum and constant as sin Theta is always 90 degrees on wire AB. Note the sync of the time scale for F and T and bingo dead give-away... OWND!!!
12. D - Absolutely definitely D with acceptor level just above valence band for p-type semiconductor
13. B - BCS theory of cooper electron pairs paring up i.e. joining together give away here is the word pairs fo electrons.. look for it
14. C - the work function for platinum is probably greater therefore more energy is required to eject it.
15. A - Electric field between two parallel plates is always constant. if they said electric field potential jesus what a question that would have been...LOL
I'll update more later
Actually the multiple choice is one fo the weirdest and trickiest for quite a while. Part B is not too bad the only interesting questions there are the Centripetal force mv^2/r applying it with magnetic force. qvbsintheta. I liked the transistor and replacement of thermionic valves...and Q27 you had a trick answer with none or no effect between intensity of light and KE only freq is proportional here.
Not a bad test certainly will differentiate in MC section more than anywhere else...
AS USUAL NO X-RAY CRYSTALLOGRAPHY for like now 6+ years there has never been a question on this area. LHC was speculated and did appear so well done to those users posting about it. Also what the heck was that question about the flexibility and strength of rubber bands..... boring.... World class paper... and your testing skills LOL... what a joke.. reading graphs might as well put a year 7 graph question in there BOS....LAME!!!!
I love Medical Physics awesome option... and great questions there too...
Enjoy