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    A ball of mass m kg moving at u m/s hits a smooth horizontal plane at an angle of x to the horizontal. The coefficient of restitution is 0.
    Find the impulse on the plane.

    Here is what I did:

    Since e=0, there is no vertical velocity, so the speed after=horizontal speed before.

    I = m(v - u)
    so I = m(u cos x + u) = mu(cos x +1)
    however the answer in the book gives something else.
    Where have I gone wrong?


    Does the book give mu\sin x?

    If so you need to draw the diagram with the components of velocity parallel and perpendicular to the plane. The velocity parallel to the plane will not change.
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Updated: November 9, 2016

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