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    I don't really get the impulse stuff in M1 (Edexcel)...
    Like for this question (June 2005, q's 2) , I did part a), but for part b), I'm not sure about the direction of the impulse and have got quite a few of these kind of questions wrong...
    Could someone explain impulse and momentum please?

    Two small steel balls A and B have mass 0.6 kg and 0.2 kg respectively. They are movingtowards each other in opposite directions on a smooth horizontal table when they collidedirectly. Immediately before the collision, the speed of A is 8 m s–1 and the speed of Bis 2 m s–1. Immediately after the collision, the direction of motion of A is unchanged and thespeed of B is twice the speed of A. Find
    (a) the speed of A immediately after the collision,(5)
    (b) the magnitude of the impulse exerted on B in the collision. (3)
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    (Original post by 29Bilal96)
    I don't really get the impulse stuff in M1 (Edexcel)...
    Like for this question (June 2005, q's 2) , I did part a), but for part b), I'm not sure about the direction of the impulse and have got quite a few of these kind of questions wrong...
    Could someone explain impulse and momentum please?

    Two small steel balls A and B have mass 0.6 kg and 0.2 kg respectively. They are movingtowards each other in opposite directions on a smooth horizontal table when they collidedirectly. Immediately before the collision, the speed of A is 8 m s–1 and the speed of Bis 2 m s–1. Immediately after the collision, the direction of motion of A is unchanged and thespeed of B is twice the speed of A. Find
    (a) the speed of A immediately after the collision,(5)
    (b) the magnitude of the impulse exerted on B in the collision. (3)
    Hi!

    All impulse is is the change in momentum.

    So in this question, to find the impulse exerted on B, you use the equation:
     I = m(v-u),



where I is impulse,

m is mass of the object,

v and u are the final and initial velocities respectively.

    Can you try the question now?

    Hope I helped.
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    (Original post by Fanta4TheBanter)
    Hi!

    All impulse is is the change in momentum.

    So in this question, to find the impulse exerted on B, you use the equation:
     I = m(v-u),



where I is impulse,

m is mass of the object,

v and u are the final and initial velocities respectively.

    Can you try the question now?

    Hope I helped.
    I got this question correct , as I took rightwards as the positive direction and then did
     I=0.2(8.8--2)

=0.2(10.8)

=2.16 Ns.

    For a different question though (January 2005, q's 1c), I did the same thing, but got -8.25 Ns as the impulse, when the answer should just have been 8.25 Ns...do you know why I got the wrong answer?
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    (Original post by 29Bilal96)
    I got this question correct , as I took rightwards as the positive direction and then did
     I=0.2(8.8--2)

=0.2(10.8)

=2.16 Ns.

    For a different question though (January 2005, q's 1c), I did the same thing, but got -8.25 Ns as the impulse, when the answer should just have been 8.25 Ns...do you know why I got the wrong answer?
    If the question simply asks for the magnitude of the impulse, just write down the positive of whatever your answer is if you come out with a negative.
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    (Original post by Fanta4TheBanter)
    If the question simply asks for the magnitude of the impulse, just write down the positive of whatever your answer is if you come out with a negative.
    Okay, thanks
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    (Original post by 29Bilal96)
    Okay, thanks
    No problem! Glad I could help!
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