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Physics help urgent watch

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    A bullet of mass 3.0*10^-2 is fired at a sheet of plastic of thickeness 0.015. the bullet enters the plastic with a speed of 200ms-1 and emerges from the other side with a speed of 50ms-1

    calculate the loss of ke of the bullet as it passes through i got 562.6

    the average frictional force exerted by the plastic on the bullet; idk how to answer this plz help
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    In normal motion we assume there is no resistive force to the bullet.

    When the bullet enters the sheet it experiences a frictional force, which causes a net force to act on the bullet, slowing it down.

    A resultant force on an object with mass will cause an acceleration.

    What is a formula for acceleration? You have enough information to calculate the acceleration (in this case, deceleration) of the bullet.

    Using this acceleration, refer to Newton's 2nd Law to obtain force
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    (Original post by yeah1106)
    ^
    Part a) use ΔE = 1/2m(v2-u2)

    Part b) use W.D = Fd

    Does that help?
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    (Original post by Alexion)
    Part a) use ΔE = 1/2m(v2-u2)

    Part b) use W.D = Fd

    Does that help?
    Actually this is much simpler :laugh:

    Use this expression for part b
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    (Original post by Alexion)
    Part a) use ΔE = 1/2m(v2-u2)

    Part b) use W.D = Fd

    Does that help?
    Thx so much i got the right answer
 
 
 
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