June 2011 G485-Fields, Particles and Frontiers of Physics

Yeah, there was another one. Where it said calulate the acceleration to be about 1x10^16 which came out to 1.2x10^16,
(then work out the time as 1x10^-9)
and then the next one where it says (use this to) now calculate the velocity to be 1.2x10^7 ms^-1
You cannot get the correct speed unless you get the acceleration correct.

Usually when they give you values, its to help candidates who don't calculate it, but it'll still allow them a chance to do the second part.
This one didn't.

(I found this out because first time run through i didn't work out the accn, used the value given, and didn't get the speed it wanted)

What happens if theres mistakes in exams? do they change anything?

Alright paper - too much writing and not enough calculation though. No quarks, radioactivity, binding energy calculations at all WTF

For the angle - pretty sure it is 73degrees - tan = F/mg
Maybe some of you got the force wrong on the previous question

The one im worrying about is the ratio question. I put 1/3 initially and then changed it to 1/27 when i realised they have different voltages. Then changed my answer to the worded one after that about 5 times >.>

Also, the electric field strength question between the two balls was tricky. I worked them out seperately and minused them. (they are acting in opposite directions)

Alright paper - too much writing and not enough calculation though. No quarks, radioactivity, binding energy calculations at all WTF

For the angle - pretty sure it is 73degrees - tan = F/mg
Maybe some of you got the force wrong on the previous question

The one im worrying about is the ratio question. I put 1/3 initially and then changed it to 1/27 when i realised they have different voltages. Then changed my answer to the worded one after that about 5 times >.>

Also, the electric field strength question between the two balls was tricky. I worked them out seperately and minused them. (they are acting in opposite directions)

I did tan^-1(1.5x10^-4/4.5x10^-4) and got like 18 degrees.

What was our KE graph like?!?!?

oh OCR, you so crazy with your impossible questions!

When my exam officer wrang OCR, they said that you could either use 0.05 metres or centimetres and you would still be awarded the marks.

I completely had to take a guess (well educated guess). I drew a straight, increasing line up to 0.08m - each 0.04m increasing by by whatever my answer to the Ek question was). Then a similar, but decreasing line for Ek between 0.08m and 0.12m.