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An object is dropped from a height of 12m.At what height is the rock kinetic energy and its potential energy be equal?

  • physics -

    assume potential energy = 0 when h = 0
    U = m g h
    U top = total energy = m (9.8 * 12)
    =

    U + Ke = U top
    so
    if U = Ke then
    U = U top /2 = m (9.8 * 6)
    so
    at h = 6 meters

    In other words, when it loses half its original potential energy, the Ke = U and that is halfway down.

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