Physics IGCSE Edexcel May 25th 2016.

Original post by kavishax

I said that because GPE=mgh and their mass and gravity remains constant, the increased height would increase their GPE. On the whole I don't think I did well on that paper though :frown:

Dammit, was the question about gaining GPE when they go up? Didn't realise it was that simple I thought it asked why they gain GPE when they go down... oops
Wait, then again the lift did say that it took passengers DOWN but never said it took them up

(edited 7 years ago)

Reply 62

iamamarxist

7

was it just me who found it really easy?

Reply 63

Original post by iamamarxist

was it just me who found it really easy?

Wasn't really that bad at all, just the question on why the wavelength of sound increases when sped up was pretty difficult

Reply 64

Jamie99qwerty

Original post by Speersy

Did everyone put light energy for the type of energy released from nuclear fisssion? I wasnt sure if it was thermal or light :s-smilie:

kinetic energy of the daughter nuclei

Reply 65

alexaorh

Original post by Speersy

I dont know myself tbh! it was just a guess, there's nothing on it in the textbook and I can't even find an answer on the internet!
But I guess the way to look at is that its basically 2 marks knocked of the grade boundary cuz barely anyone will get that right

Aha i like ur attitude! There was so much in there that none of the textbooks mentioned

Reply 66

tomtimpson

I put nuclear energy was released, stupid I know, but I just remembered reading somewhere in the CGP guide that nuclear energy was 'given off' from fission.

Reply 67

iamamarxist

7

Original post by Speersy

Wasn't really that bad at all, just the question on why the wavelength of sound increases when sped up was pretty difficult

its because their proportional, wavelength and wavespeed. think about it, the frequency is staying the same, so if the frequency is say 70Hz, if v increases, from 140 to 150, then 140=70x2 - 150=70x?

Obviously the wavelength must have increased

Reply 68

Original post by tomtimpson

I put nuclear energy was released, stupid I know, but I just remembered reading somewhere in the CGP guide that nuclear energy was 'given off' from fission.

Same! I remember nearly putting nuclear down

Reply 69

Salmonking

3

The wave equation (V= f lambda) can be used for all waves not just light

Reply 70

Ultimate Quasor

Anyone got the unofficial mark scheme?

Reply 71

Ultimate Quasor

Anyone got an unofficial mark scheme?

Reply 72

tomtimpson

Right, See number (5) on there... "Nuclear energy -- released only from nuclear reactions"

Reply 73

outgoingpopcorn

17

Original post by Speersy

Wasn't really that bad at all, just the question on why the wavelength of sound increases when sped up was pretty difficult

I used the equation wavespeed = wavelength * frequency

I am not sure if this is right, but I put that if the speed increases whilst the frequency was kept the same the wavelength would increase.
I was stuck on the question before that though.

Reply 74

jamesj477

10

What did everyone put for the pressure question on the diver? I completely ****ed up the first one, you were meant to use p1v1=p2v2 and you got something like 14000, I got 0.142...
Also for the other diver one about pressure difference, i did the equation and got 113kPa, but were you meant to subtract 101kPa from it.
Second one I did 113kPa + 101kPa = 214kPa but idk
Also the why does the refractive index not have units.... wtf. I put something along the lines of it isnt a physical thing you could measure, so it isnt a scalar or vector. Also something about you can only have it between certain numbers, you cant go beneath 1 in the refractive index.
Overall an ok paper, but with some really weird questions

Reply 75

tomtimpson

Original post by jamesj477

What did everyone put for the pressure question on the diver? I completely ****ed up the first one, you were meant to use p1v1=p2v2 and you got something like 14000, I got 0.142...
Also for the other diver one about pressure difference, i did the equation and got 113kPa, but were you meant to subtract 101kPa from it.
Second one I did 113kPa + 101kPa = 214kPa but idk
Also the why does the refractive index not have units.... wtf. I put something along the lines of it isnt a physical thing you could measure, so it isnt a scalar or vector. Also something about you can only have it between certain numbers, you cant go beneath 1 in the refractive index.
Overall an ok paper, but with some really weird questions

Surely you weren't meant to subtract 101kPa because the formula found the "pressure difference" anyway?

Reply 76