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General Thoughts: Physics (1 Viewer)

Sarthakgarg

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why is it a parabolic path rather than a linear?
I related it to Thompson's charge to mass ratio and said that the force due to electric field equals centripetal force on the electrons....
 

malcolm21

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it was like a table and it said choose the correct contribution of einsten and planck to quantum theory or something
a

btw, did anyone talk about the circuit not being closed in the electron deflection one? I dont know if thats right
 

knightus10

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I hated that last space question. Screwed me over so much. Probably got 2/6 for that. And Probs lost 3 marks on the super conductor. Gahhh how does one get the velocity of the electron?!?!? Idk. It was ok, but on the harder part of 'ok'. I guess I should be relieved that HSC is over for me :p
 

HecticLad

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I hated that last space question. Screwed me over so much. Probably got 2/6 for that. And Probs lost 3 marks on the super conductor. Gahhh how does one get the velocity of the electron?!?!? Idk. It was ok, but on the harder part of 'ok'. I guess I should be relieved that HSC is over for me :p
use the force from part a to find the acceleration, then plug acceleration into v^2=u^2+2as
 

knightus10

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use the force from part a to find the acceleration, then plug acceleration into v^2=u^2+2as
But doesn't that only apply for projectile motion. Wasn't the electron going straight to the right?
 

p0llex

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But doesn't that only apply for projectile motion. Wasn't the electron going straight to the right?
It still applies for things which aren't projectiles, but in this case the electrons have some initial velocity which we don't know.

Best way of doing it I think was using qV=1/2mv^2, answer turned out to be somewhere between 7000 and 8000
 

astroman

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That was pretty tough, and wtf there was only like 10/55 marks worth of space related questions.
 

malcolm21

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does anybody know if my reasoning that the electric circuit wasn't closed (that 2 cm gap) means electrons cant be liberated from cathode and accel towards anode? i wrote that + electrons are - charge so its deflecting wrong way
 

sy37

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For the one where you had to sketch a graph of the copper going under the magnet, am I the only one who let the decrease in velocity curve go well throgugh C and back up just before D? Because the end of the copper still touches. I think that might have tricked some people

pretty fucking hard exam imo..averaged 80% in MC for past papers, expecting like 60% here because I was barely sure.....am I the only one who got BARELY like 1-2 D's only?

Some questions were nice, others worded poorly..gg tough exam fuck
 

snail489

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I used integration for more than one question LOL i got the answer but do i get marks
heh I did this too to get the velocity of the electron as it reaches anode... pretty sure I got the correct answer but just praying that they don't deduct marks since i literally forgot about using projectile motion formulas
 

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