AQA PHYA4 ~ 13th June 2013 ~ A2 Physics

Scroll to see replies

Reply 780

MSI_10

Original post by The H

Yeah, i got that except I think i used 3 sig figs in the time

Would sig figs matter in this case?

Reply 781

Jack93o

Original post by Stellios

This means a mark of 65/72 = 100 ums?

not sure, heres the website to check out raw to ums:
http://www.aqa.org.uk/exams-administration/about-results/uniform-mark-scale/convert-marks-to-ums

they seem to vary it a bit

Reply 782

kingm

Original post by Dirtybit

Lmao... Think you've over complicated it there

Loooool.....duuuude the CYCLOTRON! I was trying to contain my laughter when I saw that :biggrin:

.

How did you find the paper?

Reply 783

S1L3NTPR3Y

Original post by The H

Yeah, i got that except I think i used 3 sig figs in the time

Cool that was my answer too :cool:

But can you remember what the part which they asked you about after was?

Reply 784

Robmarkey

Quite and easy paper, Some tricky multiple choices as usual though.
For the fields question when it was on about the angles was it 60 or 150 and then was the next bit 5pi/6? And for the graph you just had to draw was just a simple sine graph?

Reply 785

The H

Original post by MSI_10

Would sig figs matter in this case?

I don't think so

Reply 786

MSI_10

Original post by S1L3NTPR3Y

Cool that was my answer too :cool:

But can you remember what the part which they asked you about after was?

Explain why time is independent of radius?

Did PI R / V is T subbed it into r=mv/bq, radius is removed from eqn so there's the explanation?

Reply 787

foximus

Original post by flashbackto1999

no there was an equal and opposite force in either side of the coil.

look up what definition of couple is.

Reply 788

saba146

what did people put for the direction of the applied magnetic force?

Reply 789

kingm

Original post by Robmarkey

Agree with all of that but i drew a negative sine graph instead of a normal one....

Reply 790

The H

Original post by S1L3NTPR3Y

Cool that was my answer too :cool:

But can you remember what the part which they asked you about after was?

I think it was where you show that the time is independant of the radius? Or something like that

Reply 791

cooldudeman

Original post by foximus

look up what definition of couple is.

I said the couple answer. Is that correct? I had no idea on that one

Posted from TSR Mobile

Reply 792

marcolliwright

Original post by foximus

look up what definition of couple is.

Thing is surely it wouldn't be either of them then as they mean exactly the same thing? So one couldn't be wrong while the other is right? I remember putting C I think can't remember exactly what it was but it wasn't the couple or the equal and opposite forces or the "displacing the coil" option...

EDIT: Having seen the link posted by flashback I definitely didn't put C... can't remember which one I put lol

(edited 10 years ago)

Reply 793

marcolliwright

For question 5 I'm fairly certain it was 60 degrees for the first one and then 5pi/6 for the second (radians) one....

Reply 794

flashbackto1999

Original post by foximus

look up what definition of couple is.

It was the same question as a past paper, Q14. The mark scheme says A.

http://papers.xtremepapers.com/AQA/Physics/2003%20Jan/AQA-PA04-W-QP-JAN03.pdf

Reply 795

foximus

Original post by Robmarkey

it was 150 for max emf (this is when the magnet was next ppd to the field since it was rotating anticlockwise)
and pi/3 (ie 60) for max flux (as this occurs when magnet is parallel to the field

Reply 796

cooldudeman

Original post by marcolliwright

Doesnt equal and opposite forces mean that the coil will be stationary. When it is spinning, both forces are in the same direction(which is a couple), otherwise how would it spin... aduno im no genius

Posted from TSR Mobile