2016 | OCR A2 Advancing Physics B | G494 & G495 | 20th & 28th June

Boundary predictions? A* around 50 ish maybe idk

For the relativistic one, I used 2x10^8 as the value for velocity which meant gamma factor was 1.34 instead of 1.25 as I wasn't sure whether my initial calculated one was right. This then gave me a time of 3.73 not 4ns. Would I still get the marks??

For the relativistic one, I used 2x10^8 as the value for velocity which meant gamma factor was 1.34 instead of 1.25 as I wasn't sure whether my initial calculated one was right. This then gave me a time of 3.73 not 4ns. Would I still get the marks??

Question 9 I worked out rc from initial tangent, then subbed it and a value of the graph in to q0e-t/rc, is this enough for a proof as it only did one point?

Question 9 I worked out rc from initial tangent, then subbed it and a value of the graph in to q0e-t/rc, is this enough for a proof as it only did one point?

Hello! I was pretty disappointed in myself in this paper cos when doing past papers I kept getting like As and in this paper I doubt I got that here. Hopefully...HOPEFULLY I get above 40 in this paper at least. I hated the vacuum question, I just left out the last part. Sigh...

I did a similar thing, I knew that R and C around the circuit wouldn't change since the circuit wasn't altered part way through. I then used the equation V=V0e^-t/RC and rearranged to find RC at two different points along the graph. The values I got were not the same therefore RC didn't stay constant and I said this meant it wasn't exponential decay.

I have no idea if this is the ideal answer/will be reflected in the mark scheme

The vacuum question was a bit awkward. I know I fell short at the uncertainty part, like many did, but the rest of it was okay I think. It just felt uncomfortable because equilibrium is something we usually do in terms of force, rather than pressure, but s'all the same I guess. The description bit just required the hurling of terminology at the paper; something something collision, something something exchange of momentum, something something rate of change of blah blah equals force, etc.

It was made-up for by a really simple final question, methinks.

I know right? And for the last part most people I know just wrote down the area for the 30mm diameter then left it there. Also a lot of people also misread and took the diameter in the calculation as the radius. Usually I'm dreadful at explanations and great at calculations, but it was actually the opposite in this case.

i think you had to take that away from the 100kpa atmospheric pressure

Yeah I wouldn't worry too much about it. It's just the lil' stuff like this why it's so much harder to get 100% in Physics than say a Maths module. S'all gooood.

Anyways, better get back to work revisiong for the exam tomorrow.
/goodbye until G495

Yeahh I got 83kPa, resolved forces for it lmao

I concur.

I got about 170000 Pa??