AQA Physics PHYA4 - Thursday 11th June 2015 [Exam Discussion Thread]

Has anyone tried the "exam style questions" at the end of each chapter of the book? I just didn't know if they were worth doing


Posted from TSR Mobile

Yeah chapter one is alright to be honest. Some heavy notes on telescopes coming up though

I've looked at those exam style questions in the text book btw and decided against them. They seem really wordy and not actually exam like at all. I just do the summary questions and then for exam practice I'll go to actual papers.

I have for phya4 all the chapters except magnetism and emi since i cant do that chapter!
Theyre quite good for phya4 tbh and it's helped me quite a lot especially since there isn't a lot of past papers! 😀
Posted from TSR Mobile

Unfortunately yeah but its worth it!

Can someone explain how more damping than critical damping can actually mean the amplitude of oscillations is reduced less with each cycle?


Posted from TSR Mobile

Hi, can anyone explain how you know when to choose [R] or when to choose [R] as i dont know which one to use when. Thanks

Is that overdamping? whereby it takes longer to return to equilibrium. I think its because the displacement is gradually reduced but in critically damped its built to suddenly stop displacement. Not too sure if thats any help lol

Hi, can anyone explain how you know when to choose [R] or when to choose [R] as i dont know which one to use when. Thanks

Need to ask you something

last year I did PHY6X but this year I'm doing PHY6T even though they're worth different amounts of UMS. Will it still count to my final grade etc?

They are worth the same amount of UMS (out of 60). They may be different numbers of marks for the respective tasks, but they will be scaled so that the UMS gained for unit 6X and unit 6T will be the same.

The exams are worth 120 UMS each, so 60 UMS gained from unit 6 on either scheme X or scheme T will make the 300 UMS total that make up the year.


Posted from TSR Mobile

Oh ok so I'm allowed to do either

Yeah I could never understand why more damping than critical damping actually means it is free to oscillate more than critical damping!


Posted from TSR Mobile

In theory yes, although most centres enter candidates for the same scheme in both years.


Posted from TSR Mobile

It's not free to oscillate.
There is no oscillation if the damping is equal to or greater than critical.
In these cases the mass returns to equilibrium and stays there.
The only difference is that it takes longer to get there as the damping increases. This is perfectly logical, as more damping means more resistance, this means the mass moves more slowly, which means it takes longer to get to the equilibrium point.

I did PHY6X at school where as I'm doing PHY6T at a different centre now. It's probably because they only do T?

This diagram uses T for tension, but the same principle applies for R.


Posted from TSR Mobile