AQA Physics PHYA5 - Thursday 18th June 2015 [Exam Discussion Thread]

Oh yeah. I did 1.982. Does it matter?

Wasn't the abs magnitude 1.98(1) - M = 5log(25/10)
Well **** that 1 I added changes it significantly, do you think they'll accept it?

You are looking at a good grade my friend, first astro is wrong , I made the same mistake, you add 1 AU as largest distance is when its on the other side of the sun.

It's how you read it of the graph, I assume there will be a range

So is everyone now agreeing that it is 2.57 + 1 because it said the asteroid belt thing is in between Mars and Jupiter I think.. or does that not matter?

2.27x10^17 for the number of nuclei question?

2.27x10^17 for the number of nuclei question?

hmm I have no idea, I done the same as you

I got 2.35x10^17; seems pretty close, did you use your own value or the one given as show the decay constant blah blah.

Did you calculate it by taking 1 AU from 2.57AU (whatever the furthest distance was)

or did you calculate it using a triangle with base 1 AU and legnth 2.57AU and take
hypotenuse?

Yeah but in more detail eg:
Pressure is directly proportional to temperature, measure the pressure for different temperatures and plot a graph of pressure against temperature. Plot a line of best fit and extrapolate backwards until it intercepts the x axis. This temperature is absolute zero. This is supported by the fact that for a fixed volume, P=kT where k is a constant, so when P = 0, T=0. This is because at this temperature the molecules have no kinetic energy so they don't vibrate and hence don't exert a pressure on the container. 😊 that's a six mark answer

F&//cking hell, did no one else do Pythagoras for first question? We're not told that the asteroid and the Earth are at opposite sides of the Sun at any one point.

I did so blah lol i wrote in more detail, i said exactly the same word for word, except i didn't include extrapolate aha

I think I used theirs.

So what's your point?? Using Pythagoras would assume the same thing...


Posted from TSR Mobile

Yes everyones paper had R on the code. Confirmed.

Posted from TSR Mobile

F&//cking hell, did no one else do Pythagoras for first question? We're not told that the asteroid and the Earth are at opposite sides of the Sun at any one point.