AQA physics A Level Paper 3 14th June 2018 Unofficial Markscheme

Original post by noajaho11

did anyone else get 4 exactly for n?

I got 3.9 to two sf, could’ve put 4 now that I think about it

Reply 44

asol11

3

What did you guys get for the last turning points qu? (muons) I got something like 82 percent
I cant remember if it was how many had decayed or how many were left :'(

Reply 45

JakeAdam123

Original post by BTAnonymous

-273.1 i think. I found my gradient and y intercept then subbed y = 0 to find T.

Did you convert units or anything ? I got 4 and annoyed at why I went wrogm

Reply 46

willfarrar

6

82% for muon intensity?

Reply 47

asol11

3

Original post by willfarrar

82% for muon intensity?

YAY

Reply 48

Original post by kibi.coco

Pretty sure charles law is volume is proportional to temperarure

Couldn’t you just state that it was a closed system so using Charles law would be suitable?

Reply 49

J...H

14

misread that as psychology and was freaked out for a moment lmao

Reply 50

Jcvjcvjcv

9

Original post by 123medicine

Did you convert units or anything ? I got 4 and annoyed at why I went wrogm

You forgot to do v2-v1 of the volumes

Reply 51

BTAnonymous

22

Original post by 123medicine

Did you convert units or anything ? I got 4 and annoyed at why I went wrogm

i initially converted volume to meters cubed but gave me an answer which was 1000 times more negative than absolute 0 in celcius. I don't know why meters (maybe because Celsius isn't base SI??) didn't work but I just found my gradient in cm instead and got a much more reasonable answer.

Reply 52

Quantum18

6

For astrophysics:
Wavelength for the Griffith telescope is 5.5X10^-7m

Focal length 0.029 or 0.03 to 2sf

The telescope was good enough to resolve the asteroid as the angle of the asteroid was 10.8X-3 rad and the resolution of the telescope eyepiece was 3.2X10-4 rad

The black-body radiation curve I just wrote you can use Weins law to work out temperature.

The age of the universe I got 4.4X10^17 I worked that out by calculating recessional velocity using the Doppler shift equation and then used it to work out hubbles constant and 1/H is the age of the universe as H indicates that the recessional velocity is proportional to distance and therefore the the universe is expanding at a uniform rate.

The distance question regarding quasars I’m not too sure on but I think I got 32.6 times further than the most distant galaxy

Reply 53

Ladkus

Original post by rexs2000

I got A As 10^-1 cuz I converted to metres from cm

Shouldnt matter cause it said state the unit

Reply 54

Original post by willfarrar

I got N as 4 and A as x10^-7
Ruler I got 128g
B was the gradient of the graph divided by 0.15
I’ll drown in the hot bath question
Charles’ Law is pressure constant?
Measure with a measuring cylinder and make sure eye isn’t perpendicular to scale to reduce parallax error?

It wanted systematic error I think parallax is human error I’m not sure? You’re probably right though

(edited 5 years ago)

Reply 55

Ladkus

Original post by zMarshaall

It wanted systematic error I think parallax is human error I’m not sure? You’re probably right though

Parrallax is a random error

Reply 56

Graphittte

9

Original post by rexs2000

Got n as 3.9 but apparently supposed to be an integer
Also I said plot F against d then use gradient to work out k is this right

I did the same.
I think they were looking for current being the independant variable as they included the limit.
I don't think we were wrong though

Reply 57

JakeAdam123

Original post by Jcvjcvjcv

You forgot to do v2-v1 of the volumes

Oh when plotting the graph??? Thanks!!!

Reply 58

Jwazza343

2

Original post by Ladkus

Parrallax is a random error

I put measure mass with and without water, then find volume using density.
Zero scale to avoid systematic but idk

Reply 59