AQA A-level Physics Paper 3 - 3 June 2019 [Exam Discussion]

Astro

Practical bit tricky

Original post by Evil Homer

How did it go today guys?

Reply 61

daily_stoic

15

Section A, likely 15/45 marks.
Section B, likely 20 to 25/35 marks.

I did quite well on Paper 1 and smashed Paper 2 so hopefully I get an A or B overall

Reply 62

Original post by Evil Homer

How did it go today guys?

I thought it went great. There were maybe two questions I didn't get out of the entire paper, and both of them were small questions. I was really worried with how this one would turn out, because Practical is usually so iffy, but this went great for me.

Reply 63

maciek69

9

Same with turning points.

Reply 64

If anyone is wondering about 2.5 where you had to find the constant lambda for the water falling, you had to substitute the equation for capacitor decay and switch out RC for the lambda, with a time period and two values of Y of your choosing. Just thought I'd put that out there because I was super happy with myself for getting that one 😁

Reply 65

wack101

It was calm for me but i messed up the flow rate question, the one where they asked you for the procedure.

Original post by Evil Homer

How did it go today guys?

Reply 66

Trapmoneybenny

15

Astro was alright. I know for a fact i fluffed the question about why there are only two observable stars in the galaxy they gave. I said that the two spectral K stars had the same color and were dim but that was about it.

And the last question about the quasar, i went on abouy red shift when i shouldve gone on about the distance

Reply 67

Samwell88

5

Original post by JordanStewart

Astro

Practical bit tricky

No idea on that graph with the radiation, aluminium thickness

Reply 68

JordanStewart

What did you get?

Original post by Dggj_19

If anyone is wondering about 2.5 where you had to find the constant lambda for the water falling, you had to substitute the equation for capacitor decay and switch out RC for the lambda, with a time period and two values of Y of your choosing. Just thought I'd put that out there because I was super happy with myself for getting that one 😁

Reply 69

AwwA

How did everyone find paper 3 and engineering option?Is there a thread on the post exam discussion?

Reply 70

Andrew3210123

3

What i did was find the equation of the line. y=a x k^t.
Put some values in and find the values for a and k. Then i used the equation to find the time taken to halve

Original post by Dggj_19

If anyone is wondering about 2.5 where you had to find the constant lambda for the water falling, you had to substitute the equation for capacitor decay and switch out RC for the lambda, with a time period and two values of Y of your choosing. Just thought I'd put that out there because I was super happy with myself for getting that one 😁

Reply 71

Original post by wack101

It was calm for me but i messed up the flow rate question, the one where they asked you for the procedure.

that's where they wanted you to find the rate of flow of water by its volume, right? You had to let the water fall into a beaker below the nozzle, for a certain amount of time - say, 10 seconds - and then measure the volume of the water you'd caught by either measuring height of width of the beaker or using it's mass and the density of water, which it gave you. You you've got the total volume that fell in that 10 seconds, divide it by 10, and then you have the rate of flow of water in cubic meters per second. 😊

Reply 72

wack101

That is how i did and then you used ln2/T1/2 to get lamda, right?

Original post by Andrew3210123

What i did was find the equation of the line. y=a x k^t.
Put some values in and find the values for a and k. Then i used the equation to find the time taken to halve

Reply 73

computeryboi

10

Section A was not good :frown:

Reply 74

Original post by Andrew3210123

What i did was find the equation of the line. y=a x k^t.
Put some values in and find the values for a and k. Then i used the equation to find the time taken to halve

That sounds like it'd work too. The decay equation for capacitors is a universal equation for decay so it seemed to work out just fine. Made finding the half life easy, too, because you just divide Ln2 by your constant you found.

Reply 75

wack101

That's how i started but i overcomplicated it coz i thought you weren't allowed to use beaker/measuring cylinder for some reason * stupid me * so i crossed out that.

Reply 76

Original post by JordanStewart

What did you get?

it gave you the approximate value, it was asking you to verify that the actual value was close to it. I think it was something like 1.1*10^-something

Reply 77

JordanStewart