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The Physics PHYA2 thread! 5th June 2013

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Wasn't the polarisation question to explain what the scientist would discover about the wave FROM THE EARTHQUAKE based on the fact that it was polarised?

Reply 1861

lebron_23

Original post by ThomT94

On the 6 mark question, first law and second law should be the other way around. Also, bullet b's distance is not affected by its mass. It's because both accelerate towards the ground at the same rate from the same height, therefore, same time of travel, thus lower horizontal speed causes bullet to travel shorter distance in the given time.

Thank you very much for your input, I will make changes to my original post.

Reply 1862

Davelittle

Original post by trentjoseph007

Thats means its different form the double slit one, like most people r explaining.

what people are explaining is right

Reply 1863

Davelittle

Original post by VV.KKGSR

The fact that it was a transverse wave was given in the question, so even i'm not sure where the 2 marks would have come from?
I just put it will be a secondary seismic wave which travels through parallel planes

Posted from TSR Mobile

Polarised so must be transverse?

I put seismic s waves as well, that should be a mark

Reply 1864

Aarongreatbanks

For the phase difference I put

"90 degrees out of phase"

"270 degrees out of phase"

Is this okay or will I not get the marks as I said "out of phase"

Reply 1865

.raiden.

Original post by lebron_23

Thank you very much for your input, I will make changes to my original post.

When its finalised let me know which page its on so I can quote it in the op :smile:

Reply 1866

Aarongreatbanks

Original post by .raiden.

When its finalised let me know which page its on so I can quote it in the op :smile:

For the phase difference I put

"90 degrees out of phase"

"270 degrees out of phase"

Is this okay or will I not get the marks as I said "out of phase"

Reply 1867

masryboy94

i think you would say that since it is transverse, you would limit the vibration to oscilliate in one direction perpendicular the wave travel (1 mark) hence the scientist could deduce where the earthquake will be directed at (1 mark)

Reply 1868

.raiden.

Original post by Aarongreatbanks

For the phase difference I put

"90 degrees out of phase"

"270 degrees out of phase"

Is this okay or will I not get the marks as I said "out of phase"

I think you will. I put that too?

Reply 1869

Hullo

Original post by lebron_23

I've just about managed to finalise the mark scheme now, but as it says, I think I've given an extra mark to one of the questions somewhere. Again, any corrections are welcome and greatly appreciated.

EDIT: I'm also still clueless as to what the second part of question 7 was, I think it was the intensity graph, but not too sure.

EDIT^2

: Its now complete, thank you .raiden. and HenryD for clearing that up.

7a - sure wavelength will get the mark? I thought coherence was strictly: constant/fixed phase difference.. I just saw that on the mark scheme highlighted/underlined loadss of times.. I could be wrong just thought otherwise

Reply 1870

HenryD

Original post by Aarongreatbanks

For the phase difference I put

"90 degrees out of phase"

"270 degrees out of phase"

Is this okay or will I not get the marks as I said "out of phase"

That would be fine I'd think.

Original post by VV.KKGSR

You'll have to state why polarisation means that it must be transverse and then say SSW I would think.

Reply 1871

masryboy94

Original post by Aarongreatbanks

For the phase difference I put

"90 degrees out of phase"

"270 degrees out of phase"

Is this okay or will I not get the marks as I said "out of phase"

i put that too because they both are out of phase since 90 and 270 are not a whole number multiple of 360 degrees

Reply 1872

Aarongreatbanks

Original post by .raiden.

I think you will. I put that too?

I don't think they'd be so harsh it is correct in my eyes I just wanted to see your opinion?

Reply 1873

.raiden.

Original post by masryboy94

In that case I put the effect of the seismic wave can only be seen in one direction is a mark? Probably too vague I guess

Reply 1874

kingmango

Has anyone got the paper yet?

Reply 1875

trentjoseph007

Look at figure 2 ... Thats what happens .. Not white central fringe .. or first order continuous spectra.

EDIT: This is the last question on the paper.