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    If anyone uses the flashcard app Anki, here is my PHYA4 deck - didn't write it with the intention to share (so some questions might not have obvious answers etc) but why not I guess..

    https://drive.google.com/file/d/0B8K...ew?usp=sharing
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    I got a tip from a guy on an A level physics facebook page:

    before the exam even starts, ask for extra paper!! It'll help, The time you spend waiting for the invidulators to walk to the front and get it will be wasted. Do rough work on there for the MCQ's as there's never enough space
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    Can someone explain how the answer is B?
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    (Original post by TheLifelessRobot)
    Can someone explain how the answer is B?
    Mass = Rate x density = 0.2kg/s

    Velocity = Rate/cross section = 0.28m/s

    Momentum = mv = 0.056Ns
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    (Original post by thomas42)
    Mass = Rate x density = 0.2kg/s

    Velocity = Rate/cross section = 0.28m/s

    Momentum = mv = 0.056Ns
    Thanks
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    Can someone plz help me with this question. Why is the answer A, and not B or even C?
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    (Original post by koolgurl14)
    Can someone plz help me with this question. Why is the answer A, and not B or even C?
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    It can't be C cos the field is horizontal as well so no force is exerted?
    And I guess it's not B cos if you use Fleming's Left Hand rule, the forces don't actually act as a couple as they point towards each other.
    Not completely sure but that's my take on it
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    (Original post by ManOfJustTin)
    It can't be C cos the field is horizontal as well so no force is exerted?
    And I guess it's not B cos if you use Fleming's Left Hand rule, the forces don't actually act as a couple as they point towards each other.
    Not completely sure but that's my take on it
    Yh I see what you mean but the forces will be point away from each other is that what you meant?
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    (Original post by koolgurl14)
    Yh I see what you mean but the forces will be point away from each other is that what you meant?
    I thought it was towards. I must be doing the stupid hand rule wrong then sorry 😅
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    (Original post by ManOfJustTin)
    I thought it was towards. I must be doing the stupid hand rule wrong then sorry 😅
    Nah the forces do point towards each other
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    (Original post by cjlh)
    Nah the forces do point towards each other
    What I am confused now are we using left hand rule ? is the current finger not up because we do it based on conventional current, god this is confusing why do i keep doing this wrong
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    dw guys ill be lowering the grade boundaries for you all im so screwed
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    (Original post by koolgurl14)
    What I am confused now are we using left hand rule ? is the current finger not up because we do it based on conventional current, god this is confusing why do i keep doing this wrong
    If we consider the closest wire, the current finger (middle) should point up with the first finger pointing in the field giving you motion inwards.
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    (Original post by koolgurl14)
    What I am confused now are we using left hand rule ? is the current finger not up because we do it based on conventional current, god this is confusing why do i keep doing this wrong
    Just remember this and you should be fine. Left hand rule for protons and current
    Right hand rule for Generators and electrons.
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    (Original post by SirRaza97)
    Just remember this and you should be fine. Left hand rule for protons and current
    Right hand rule for Generators and electrons.
    With current do you mean conventional current? if so in the questions is it a conventional current or electron direction that they are showing us?
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    The only positive thing about tomorrows exam is I can catch up on sleep.
    Lets just say im unprepared for this.
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    (Original post by koolgurl14)
    With current do you mean conventional current? if so in the questions is it a conventional current or electron direction that they are showing us?
    Ive done all the papers and have always used LHR for current. Thats conventional current. I do not think itll be any different. Be wary though if they state otherwise in the question though
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    (Original post by koolgurl14)
    With current do you mean conventional current? if so in the questions is it a conventional current or electron direction that they are showing us?
    As far as I know, LHR works for both electron flow and conventional current flow, since - after all - conventional current flow is actually opposite to the direction of the electron flow.

    Your left hand and right hand are non-superimposable mirror images, the rule works for both the proton and electron scenario.
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    When you can't sleep tho :/// lol
    Gonna flop physics...
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    Good luck everyone 👍
 
 
 
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