A2 (Edexcel) Physics Unit 4 'Physics on the Move' - 24th January 2012

58/80 normally for A* isn't it?
50/80 is impossssible i think, thats 30 marks :O

Varies from paper to paper an A has been 53 before but most the time it's high 50's. I thought this paper was much harder than anything I've seen before so I presume it'll drop to around 53 if not lower. Only guessing though, take it with a pinch of salt.

Varies from paper to paper an A has been 53 before but most the time it's high 50's. I thought this paper was much harder than anything I've seen before so I presume it'll drop to around 53 if not lower. Only guessing though, take it with a pinch of salt.

Very hard paper....
I kept on getting 200hz for the frequency question... how were you supposed to get 20?!

It has never been in the high 50's, it has always been in the low/mid 50's, the A* grade is usually high 50's at about 58-59. I reckon this paper will be one grade lower than it usually is if that makes sense so an A* would be the equivalence to an A grade at about 53/80 and an A grade will be the equivalent to a B grade etc.

I am calling this paper: a wordy bitch.

For the question you ask about, I too could only get 200hz.

You had C=500pF and R=10 Mega ohms

I did this...



$Q=IT$ so subtitute in to get:

$V=IR$ and substitute to get:

cancel to get:

so:

$T = 500E^{-12} \times 10E^6[br]T= 0.005$



so

$F=200Hz$

The only way I could see myself getting 20 Hz is if the Resistance had been printed incorrectly, and was meant to be 100 Mega ohms or the solution should have been 200Hz!

Possible I could be wrong though!

for the vinyl disc question i wrote v=rw(omega). is said r decreases and omega is constant so v must decrease and so the bumps are closer together so that the time taken by the head to pass over each bump is the same (so that the music is played at the same speed). anyway else who thought/wrote this ???

for the vinyl disc question i wrote v=rw(omega). is said r decreases and omega is constant so v must decrease and so the bumps are closer together so that the time taken by the head to pass over each bump is the same (so that the music is played at the same speed). anyway else who thought/wrote this ???