AQA A-level Physics Paper 3 (7408/3) - 15th June 2023 [Exam Chat]

Is anyone here able to send the 2022 paper 3 both 3A and 3B turning points? I am not sure if it is allowed or not but I did not find it anywhere online

Reply 5

adkc23

6

Do we have to know in depth content from paper 1 and 2 for paper 3. Seen some questions where they ask for phase difference but its only a couple marks.

Reply 6

Cesci

6

I have both the papers, at my college the teachers gave it to us. IDK if Im allowed to share them, but I haven’t heard anything saying I can’t

Reply 7

ricor0006

4

Original post by Heisenberg66

Is anyone here able to send the 2022 paper 3 both 3A and 3B turning points? I am not sure if it is allowed or not but I did not find it anywhere online

I don't have the papers but this website has a bunch of questions.

https://www.accesstuition.com/

Reply 8

Abdullah05

5

Original post by Heisenberg66

Is anyone here able to send the 2022 paper 3 both 3A and 3B turning points? I am not sure if it is allowed or not but I did not find it anywhere online

send me ur email. Ill send it to u

Reply 9

Original post by Abdullah05

send me ur email. Ill send it to u

Just sent you on a private chat, thank you so much!!

Reply 10

moonlight2460

hi can anyone explain the difference between absolute uncertainty and uncertainty, if a ruler goes up by 1 mm would you say that the absolute uncertainty is half this value so +-0.5mm?

Reply 11

Original post by moonlight2460

hi can anyone explain the difference between absolute uncertainty and uncertainty, if a ruler goes up by 1 mm would you say that the absolute uncertainty is half this value so +-0.5mm?

Uncertainty is just a general name for both percentage uncertainty and absolute uncertainty.

The ruler's absolute uncertainty would be +- 0.5mm as it is a measurement and so the ABSOLUTE uncertainty is half the resolution.

In case of converting between different units (such as speed for example that consists of distance and time) you would use a percentage uncertainty and then time the percentage by the result which would give you the total absolute uncertainty

Reply 12

moonlight2460

Original post by Heisenberg66

Uncertainty is just a general name for both percentage uncertainty and absolute uncertainty.

The ruler's absolute uncertainty would be +- 0.5mm as it is a measurement and so the ABSOLUTE uncertainty is half the resolution.

In case of converting between different units (such as speed for example that consists of distance and time) you would use a percentage uncertainty and then time the percentage by the result which would give you the total absolute uncertainty

can you elaborate more on that last bit?

Reply 13

moonlight2460

In relation to a question, a student has a diffraction grating marked 3.5x10^3 lines per m, first two questions ask for the % uncertainty and grating spacing which was 2.9% and 0.29mm, the third questions asks for the absolute uncertainty in the value of the spacing of which the answer is +- 0.01 mm can someone help me with this?

Reply 14

Original post by moonlight2460

can you elaborate more on that last bit?

Yes, so let's say you are looking to calculate the uncertainty of a speed from distance and time.

Let's say the distance is 10m with an absolute uncertainty of +-2m
The time is 5s with an absolute uncertainty of +-1s

Obviously, to calculate the actual speed you do 10/5 = 2ms^-1
But then to calculate the uncertainty you need to convert to a percentage uncertainty as the units of distance and time don't match.

2/10 * 100 = 20%
1/5 * 100 = 20%

Now to get the percentage uncertainty of speed you ADD the percentages. You can NEVER subtract the percentage uncertainties.

20 + 20 = 40%

Now to find the absolute uncertainty of the SPEED you do 0.4 * 2 = +-0.8 ms^-1

Reply 15

Orlando777

4

I reckon section a will be on Magnetic fields as it did not come up on the second paper and its a pretty big topic

Reply 16

Original post by Orlando777

I reckon section a will be on Magnetic fields as it did not come up on the second paper and its a pretty big topic

My thoughts exactly

Reply 17

moheat13