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    (Original post by honour)
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    Just use Impulse =m(v-u) but be careful with the signs. The impulse on A and the impulse on B cant both be positive since they act in opposite directions

    I would let the right direction be positive. Which means the impulse on A equals  \displaystyle -\frac{7mu}{2} since its acting to the left.

    Going by your diagram im assuming thats what the problem is.
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    (Original post by DylanJ42)
    Just use Impulse =m(v-u) but be careful with the signs. The impulse on A and the impulse on B cant both be positive since they act in opposite directions

    I would let the right direction be positive. Which means the impulse on A equals  \displaystyle -\frac{7mu}{2} since its acting to the left.

    Going by your diagram im assuming thats what the problem is.
    Hey, thanks for your response! So if after rearranging the impulse equation for A, I get u = 4/3v What should I do then?
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    (Original post by honour)
    Hey, thanks for your response! So if after rearranging the impulse equation for A, I get u = 4/3v What should I do then?
    hmm i didnt get that answer, post your workings

    also your answers will be in terms of u
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    (Original post by DylanJ42)
    hmm i didnt get that answer, post your workings

    also your answers will be in terms of u
    I realised I got one of the signs wrong, sorry. Here's my working


    I've assumed the direction of V to be to the right, because it doesn't tell us in the question
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    (Original post by honour)
    I've assumed the direction of V to be to the right, because it doesn't tell us in the question
    yea thats fine, you can let the positive direction be whichever way you like.

    the velocity of A before the collision is (-2u) not (-u), it should read  \displaystyle I = 2mv + 4mu
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    (Original post by DylanJ42)
    yea thats fine, you can let the positive direction be whichever way you like.

    the velocity of A before the collision is (-2u) not (-u), it should read  \displaystyle I = 2mv + 4mu
    Right, thanks for pointing that out. I've got it all sorted now. VA = 1/4u and VB = 1/2u.

    Thanks so much for your help Dylan, you've been brilliant! :thumbsup:
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    (Original post by honour)
    Right, thanks for pointing that out. I've got it all sorted now. VA = 1/4u and VB = 1/2u.

    Thanks so much for your help Dylan, you've been brilliant! :thumbsup:
    yep, well done

    no problem
 
 
 
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