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2016 Official AQA New Spec AS Level Physics Paper 1 - 24th of May 2016 Watch

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    The force isnt constant because as the speed reduces less air will enter the engine per unit time and hence less change in mass..something along those lines
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    (Original post by datguy1999)
    for one mark that just seemed like the logical thing to do, i am waiting for someone to tell me if im wrong, btw what did you get for the resistance of the cable in the next question
    Yhh th is the wrong thing to do you had to do 1.2/23.2x1.5 to get voltage across it then do the voltage calculated over 1.2 to get current
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    (Original post by MarioMash808)
    I've been editing the original one, here's what I have so far.
    https://docs.google.com/document/d/1...it?usp=sharing
    Hey i saw your ms ans wanted to ask bout tht wavelength question as i used 12cm as my wavelength but did everything else how many marks would i lose for that one cus im pretty sure id get ft and 2 m marks but im pretty sure wavelength was 12cm
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    (Original post by Usamajk)
    how did people solve the 5 mark frequency question?
    It wasn't 5 marks was it? I thought it was just 2:
    1.Measure wavelength
    2.F=c/lambda
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    (Original post by MHD30)
    It wasn't 5 marks was it? I thought it was just 2:
    1.Measure wavelength
    2.F=c/lambda
    yer it was 5... I think because you has to measure and then take account for how many wavelength you had measured.

    thou tbh I thought the weighting of the paper was a bit weird, like some hard questions were very few marks and you got 5 marks for that!?
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    (Original post by MarioMash808)
    I've been editing the original one, here's what I have so far.
    https://docs.google.com/document/d/1...it?usp=sharing
    Don't remember which number this was but the question was:

    A wire has a resistance 0.070 ohms and length 0.5m. Calculate the diameter considering the resistivity of this material is 9.7*10^-8.

    The answer was: Substitute your values into the resistivity formula:

    p=(RA/L) aka 9.7*10^-8=(0.070*A)/0.5

    Rearrange to find A: (9.7*10^-8)*0.5/0.070=6.929*10^-7=A

    Then rearrange A=(pi*diameter^2)/4 to find diameter:

    √ ((6.929*10^-7*4)/pi)=diameter

    hence diameter=9.39*10^-4 metres
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    (Original post by MathsMPhys)
    The force isnt constant because as the speed reduces less air will enter the engine per unit time and hence less change in mass..something along those lines
    Thats what i put but people saying , it was because velocity is vector thing , and direction is changing
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    What will an A and B be , cant stop thinking about this paper , i think A will be 52 B 46
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    (Original post by TheFrogMan)
    I reckon after the exam they should put you in a room for half an hour to realize all the stupid mistakes you made and then give you a clear paper after to redo it. So many stupid mistakes...
    I feel your pain, I made so many dumb mistakes that I realized after but my brain decided to switch off during parts and what's worse I never read most of the questions fully and went on assumptions
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    Also what did people get for the maximum frequency of the photon? I think I got 8.997x10^23Hz
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    (Original post by DEWR98)
    Also what did people get for the maximum frequency of the photon? I think I got 8.997x10^23Hz
    I got something x10^24 i think
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    What do u think the grade boundaries will be like?
    Also predictions for paper 2?
    I think it will definitely be more maths based with moments projectiles and refraction/snell's law and optical fibres. Is electricity likely to come up again or particles?
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    I thought that after the exam the grade boundary would be 65/70 for an A but since everyone has found it extremely difficult and there is a lot of debate over certain questions I feel like the A boundary would be somewhere in the lower 50's.
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    For example the question about why two photons were emitted rather than one... people chose the obvious ' it applies for the conservation of energy and momentum' but if 1 photon was emitted energy could still be conserved. This is were I put the fact that the photons travel in opposite directions to conserve momentum but then one could say that a photon has no mass hence the momentum idea is just thrown away...
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    (Original post by Al_YG)
    For example the question about why two photons were emitted rather than one... people chose the obvious ' it applies for the conservation of energy and momentum' but if 1 photon was emitted energy could still be conserved. This is were I put the fact that the photons travel in opposite directions to conserve momentum but then one could say that a photon has no mass hence the momentum idea is just thrown away...
    2 photons are produced because you have two different anti particle pairs being annihilated so you get the photons which correspond to the annihilation of those particles..thats what i put because usually in anjihilation of an antiparticle pair its 1 photon... i think anyway..and what bout tht 5mark wavelength question i used 12cm i heard people put 11.8 cm thinking if i do get the measurement wrong they may still give me ft and method marks
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    (Original post by Al_YG)
    For example the question about why two photons were emitted rather than one... people chose the obvious ' it applies for the conservation of energy and momentum' but if 1 photon was emitted energy could still be conserved. This is were I put the fact that the photons travel in opposite directions to conserve momentum but then one could say that a photon has no mass hence the momentum idea is just thrown away...
    Your slightly incorrect with your statements.

    Momentum must be conserved relative to any inertial frame of reference. Let's take our frame of reference to be the point of collision between the electron and positron, then, here, the total momentum before the collision would be zero as the electron and positron are moving towards each other in the opposite direction. It is hence not possible to only produce one photon because you need two photons that are travelling in opposite directions at the same speed to then have zero momentum after the collision too.

    As for the maseless argument, photons are considered massless, because their mass is very small indeed. This does not mean that they don't have any. Hence, even if one photon was produced, the total momentum after collision would never quite be zero (effectively breaking physical laws that we know must hold).
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    (Original post by Al_YG)
    I thought that after the exam the grade boundary would be 65/70 for an A but since everyone has found it extremely difficult and there is a lot of debate over certain questions I feel like the A boundary would be somewhere in the lower 50's.
    Pretty sure the boundary for an A will be about 47-49.
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    Lets focus on Paper 2 now. There's a paper 2 thread for the 9th of June.
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    (Original post by Someboady)
    Lets focus on Paper 2 now. There's a paper 2 thread for the 9th of June.
    I agree,and I am quite worried about it.


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    Can I just get some last minute re-assurance, for the 5 marker question I was soo happy that came up during the test as the day before I watched a youtube video on it, but amidst the excitement I forgot that the wavelength would be across 3 nodes not 2 I messed up on that. I did everything else correctly (wasn't much else to do tbh) but I remember putting 5.9 instead of 12.8 or something. How many marks do you guys feel I'v lost. This and the diameter question are the only ones that are really cause for concern at this moment in time.

    Cheers
 
 
 
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