Hey there! Sign in to join this conversationNew here? Join for free

The Physics PHYA2 thread! 5th June 2013 Watch

  • View Poll Results: What mark do you think you got out of 70?
    0-20
    6
    3.00%
    21-40
    12
    6.00%
    41-50
    29
    14.50%
    51-60
    79
    39.50%
    61-70
    74
    37.00%

    Offline

    2
    ReputationRep:
    here are all the 6/8(when including diagram) markers so far:
    specimen- double slit experiment
    jan 09 - velocity of a ball
    jun 09 - measuring an unknown mass
    jan 10 - young's modulus
    jun 10 - gymnast an energy loss/types of energy
    jan 11 - stationary waves
    jun 11 - double slits
    jan 12 - diffraction grating
    jun 12 - determining spring constant
    jan 13 - formation of stationary waves (again)

    jun 13 ???????????????????????????????? ???????

    Look at individual ones for more info. but i guess it will probs be waves or slits/diffraction grating
    Offline

    5
    ReputationRep:
    (Original post by BenChard)
    jun10 q3d
    Talk about polaroid sunglasses. And they reduce glare from the reflection because they polarise the incident rays. Is that ok?
    Offline

    13
    ReputationRep:
    (Original post by BenChard)
    jun10 q3d
    The question about uses of polarising filter? o.O
    Offline

    13
    ReputationRep:
    (Original post by StalkeR47)
    The area under the curve (is the triangle which is given by a=1/2ab). Your a is the x-axis and b is the y-axis. Or something like that. Just replace the energy stored equation with the area and replace those delta L and K with the a and b. Is that ok?
    Thank you! I completely forgot about that.
    Can you simply prove it by using a graph though?
    Offline

    2
    ReputationRep:
    (Original post by x-Sophie-x)
    I did the same thing as you :L

    X and Z are in phase because they are 'doing the same thing at the same time'
    X and Y are antiphase because they are doing different things.
    This applies because the wave is a stationary wave :')
    Aah right cheers, didn't spot that, still quite a terrible question though :X lol.
    Offline

    0
    ReputationRep:
    (Original post by yorkshire.lad)
    Done all the past papers, this question was the only one really that made no sense at all.



    The question asked to state the phase relationship between x and y, and x and z, I calculate that X and Y are 135 degrees out of phase, and x and z are 315 degrees out of phase. However the mark scheme for the June 2012 paper states that the phase relationship between x and y is completely out of phase/180 degrees, and between x and z is 360/0/2pi radians completely in phase.


    It makes no sense at all? Please help.
    Specification states that we should be able to know if a wave is 180^{o} // \pi out of phase.I don't think they want you to know how out of phase are. If you are ever faced with a question like this though, it's either in-phase or 180^{o} // \pi out of phase.
    Offline

    0
    ReputationRep:
    [QUObecauseorkshire.lad;42967497]Done all the past papers, this question was the only one really that made no sense at all.



    The question asked to state the phase relationship between x and y, and x and z, I calculate that X and Y are 135 degrees out of phase, and x and z are 315 degrees out of phase. However the mark scheme for the June 2012 paper states that the phase relationship between x and y is completely out of phase/180 degrees, and between x and z is 360/0/2pi radians completely in phase.


    It makes no sense at all? Please help.[/QUOTE]
    Its because its a stationary wave. If two points are on the same side of the stationary wave (x and z) then they are always in phase. If the are on differnt sides, then they are always out of phase. It doesnt matter about the spacing bettween them because its a stationary wave, just which side they ard on.
    I hope that makes sense.
    Offline

    5
    ReputationRep:
    (Original post by Edorrans)
    Yeah thats great thank you! Could you explain what the difference would be between the white light and the red laser in that drawing?
    White light is composed of different colours so the interference pattern seen would be a spectrum with the middle maximum to be the white and brightest and further apart fringes to be less bright and colourful (red and blue/violet). With a red light, since red light has the longest wavelength. This about the equation w=D lambda/s. Increasing the lambda (red light) will clearly increase the fringe pattern seen. Is that ok?
    Offline

    2
    ReputationRep:
    (Original post by Raimonduo)
    Specification states that we should be able to know if a wave is 180^{o} // \pi out of phase.I don't think they want you to know how out of phase are. If you are ever faced with a question like this though, it's either in-phase or 180^{o} // \pi out of phase.
    (Original post by orangutans1995)
    [QUObecauseorkshire.lad;42967497]Done all the past papers, this question was the only one really that made no sense at all.



    The question asked to state the phase relationship between x and y, and x and z, I calculate that X and Y are 135 degrees out of phase, and x and z are 315 degrees out of phase. However the mark scheme for the June 2012 paper states that the phase relationship between x and y is completely out of phase/180 degrees, and between x and z is 360/0/2pi radians completely in phase.


    It makes no sense at all? Please help.
    Its because its a stationary wave. If two points are on the same side of the stationary wave (x and z) then they are always in phase. If the are on differnt sides, then they are always out of phase. It doesnt matter about the spacing bettween them because its a stationary wave, just which side they ard on.
    I hope that makes sense.[/QUOTE]

    Thank you both, if it comes up tomorrow atleast i know now
    Offline

    0
    ReputationRep:
    JAN 2012 question 7b and 7c ???
    Offline

    0
    ReputationRep:
    Thank you both, if it comes up tomorrow atleast i know now
    Hope it comes up, I love waves.
    Offline

    13
    ReputationRep:
    (Original post by yorkshire.lad)
    Aah right cheers, didn't spot that, still quite a terrible question though :X lol.
    I agree. Took me a long while to work out why you dont work out the actual phase difference >.<
    Offline

    0
    ReputationRep:
    How would I do 6bii on June 12?
    Offline

    5
    ReputationRep:
    (Original post by x-Sophie-x)
    Thank you! I completely forgot about that.
    Can you simply prove it by using a graph though?
    Yep you can. If you have a line drawn, for extension against the force. so, e=1/2 x F x Delta L gives the energy stored in the extension. But, I remember this was question on that. They gave you a graph did not they? So you do not need to prove by drawing the graph unless they have not given you and you have a space.
    Offline

    1
    ReputationRep:
    it's 2d not 3d sorry!!
    Offline

    0
    ReputationRep:
    I hate physics!!!
    Offline

    13
    ReputationRep:
    (Original post by StalkeR47)
    Yep you can. If you have a line drawn, for extension against the force. so, e=1/2 x F x Delta L gives the energy stored in the extension. But, I remember this was question on that. They gave you a graph did not they? So you do not need to prove by drawing the graph unless they have not given you and you have a space.
    Ooh there's a past question on this already? Didn't realise that, haven't done all the papers
    Offline

    5
    ReputationRep:
    (Original post by mikey2912)
    I hate physics!!!
    I love physics! Guys!!!!! Thumbs up if you agree with me!
    Offline

    0
    ReputationRep:
    (Original post by Raimonduo)
    Hope it comes up, I love waves.
    When it says 'the knot becomes motionless', you want to immediately think back to the basics of stationary and progressive waves, and what stationary waves consist of and how they've formed. When it says knot, it implies node, and as the standard definition of a node states: "A node is fixed point in a stationary wave where there is no particle vibrations and the amplitude is 0." Thus, linking it back to the question, it's a simple "how is a stationary wave formed", in the context of a rope.

    Hope that helps a little .
    Offline

    2
    ReputationRep:
    (Original post by SAS18)
    here are all the 6/8(when including diagram) markers so far:
    specimen- double slit experiment
    jan 09 - velocity of a ball
    jun 09 - measuring an unknown mass
    jan 10 - young's modulus
    jun 10 - gymnast an energy loss/types of energy
    jan 11 - stationary waves
    jun 11 - double slits
    jan 12 - diffraction grating
    jun 12 - determining spring constant
    jan 13 - formation of stationary waves (again)

    jun 13 ???????????????????????????????? ???????

    Look at individual ones for more info. but i guess it will probs be waves or slits/diffraction grating
    I agree that one of the wave ones seems like the most likely option. However, it seems that this year the examiners are trying to be creative across all the boards, so thus far I have found that "expect the unexpected" is a phrase to live by (I mean, look at the six-marker for unit 1). SO... the real question is what would you least expect?
 
 
 
  • See more of what you like on The Student Room

    You can personalise what you see on TSR. Tell us a little about yourself to get started.

  • Poll
    What's your favourite Christmas sweets?
  • See more of what you like on The Student Room

    You can personalise what you see on TSR. Tell us a little about yourself to get started.

  • The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

    Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

    Quick reply
    Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.