AQA GCSE Physics - P1 - 25th May 2016 - Official Thread

Any idea on how to do this question?
I'm so bad at drawing reflected rays or refraction, do you think it is likely to come tomorrow?

Please could someone define ''virtual images' and 'real images'??

Someone please break down a 6 marker on the Big Bang please

Any idea on how to do this question?
I'm so bad at drawing reflected rays or refraction, do you think it is likely to come tomorrow?

It would most likely be on what is the Big Bang? What provides evidence? (Or something along the lines of that)

The Big Bang theory states that the universe started from an initial point and then started to rapidly expand.

Cosmic microwave background radiation provides evidence for this as there is microwave radiation all over the observable universe. Microwaves are a form of EM radiation, and it's thought that shortly after the Big Bang there was infrared radiation too due to intense heat, this wave stretched to become microwaves, and so can only be proved by the Big Bang as the theory is that the universe is expanding

There is also the idea of red shift. All galaxies are showing red shift. This is where light from distant galaxies moves towards the red end of the spectrum, and so the observed wavelength is increased. This therefore shows that the galaxies are moving away from Earth. The further away the galaxies the bigger the redshift, which means they are travelling away further. This therefore provides evidence for the Big Bang theory.

I did this very quickly so there may be some errors, but I hope this gave you a nice little insight on it all

Thx also to clarify: shortly after the Big Bang there was gamma rays which had stretched to form microwaves which take up the universe today

I'm pretty sure it was IR waves and not gamma, their wavelength is well too small

Yeah Big band could be a 6 marker or comparing power stations or overhead and underground powerstations

what's cosmic background radiation could you tell me a bit about it if you could please

Does anyone have the mark scheme?

I think they're constructing one at the moment at www.gcseanswers.com under the physics section.

I'm not too keen on how it's shaping up at the moment...