AQA Physics PHYA4 - 20th June 2016 [Exam Discussion Thread]

How did people find june 13, i thought the way they did the capacitor question was difficult, also the charge traveling in a semicircle dee questions were pretty tough comparitively....but for some reason the boundaries were standard.....

I see, I'm sure it can't get any worse than June 2015 though, let's hope it isn't harder

I actually found that paper okay, time wise i struggled but the paper was okay......was it the one with the cone on the string?

And yeah maybe the 13 paper wasnt too bad.....i just have a problem where if i cant do a question i refuse to move on until i get it....i literally spent 30 minutes on the 7 mark capacitor question.....i should probably not do that lol

Hi, can someone help me? I'm struggling to know when to use the actual direction of current (- to +) and when to use conventional current (+ to -). From what I can tell, we need to use the actual direction of current in electric field questions, and conventional current in magnetic field questions... can someone verify this or explain what to do? Thanks.

Ah, yeah I'm in the same boat, the revision tips provided to us are few and far between, and a bit useless. I always do past papers under exam conditions to get a good read of where I am in terms of preparation. Although I should probably only stick to this method when I'm fresh, like I would be in an exam, I think I literally sighed out loud when I got to the 6 marker, which obviously isn't the mind set to be in :-)

Yeah the ISA's are ridiculous, especially if your in a school/college that doesn't cheat lol

Ah well, best find out where I went wrong and then start Biology revision, I really wish I'd have done further maths too rather than biology.

With those A levels are you applying for physics or engineering?

Physics at Warwick (A*AA), unless of course the ISAs drag my Physics grade down to a high B and that renders me inadequate, in which case I'll be going to Surrey (AAB). I'm actually gonna have to average an A* over Unit 4 and Unit 5 just to get said A, regardless of that fact that I got As in both Unit 1 and 2.

So what are you applying for and where?

Ha I'm in exactly the same boat, I ended up with B's last year and I was hoping that I could resit unit 2 to bump them up, but the paper was horrendous so going to pretty much have to get A* in both 4 & 5..

I'm applying to physics at Lancaster and need AAA...

I nearly applied to surrey as insurance but didn't think I could afford the prices, I've been advised against going to unis in expensive housing areas because if I take it to PHD the expenses become quite difficult to deal with. I suppose that's a worry for another day.

Also need near perfect C3 & C4 after my poor M1 performance... definately doable just cant slip up. Next week is going to be interesting, got bio5, C3,C4 and phya4. I'm sure your schedule is just as 'fun' with further maths?

Only exam I've had so far is M2, still got D1, Unit 4, C3, NM, C4, FP2 and Unit 5 in that order

From what I hear it's pretty common that people do their PHD at an entirely different University to the one they did their degree at (so there's still a chance I can live that Oxbridge life if I do well enough in undergrad). But yeah, I don't think you need to worry much about managing PHD finances this early on considering how you might end up somewhere completely different anyway

Yea a lot of people do their Phd at Oxbridge, so far I'm hoping to do something quantum computing related for my phd

hey guys, Im struggling to get my head around electric potential. I dont quiet understand what it is, even though I know the definition. For example, if a planet has a gravitational potential of -100J/kg^-1 what does this acctually mean?

It is the work done per unit mass/charge to move it from infinity to a point


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I understand the definition, but if something has a gravitational potential of -100J/kg, what does it mean and why is it negative?

I understand the definition, but if something has a gravitational potential of -100J/kg, what does it mean and why is it negative?

Its negative because its zero at infinite and reduces as range decreases.

In terms of what it is, I have an idea but it may not be correct

I see it as when an object first enters a gravitational field, the force of gravity acts on the object, the potential energy is the amount of kinetic energy used to get it to this point.

Similar to how a compressed spring has elastic potential, it is the energy that an object will have when the spring has returned to its equilibrium.

It is negative because it is energy that it has used to get to the point in the field it is at. So it is almost in energy debt, and will return to infinite when work is done on it that is equivalent to its energy debt (potential energy)

Could be completely wrong but it sort of makes sense to me.

Yhh I kinda get what your saying. Becasue like you said its the KE to get to a point, so the work done.
Thanks

I understand the definition, but if something has a gravitational potential of -100J/kg, what does it mean and why is it negative?