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The Conservation of Mechanical Energy help1?

A 47.0 g golf ball is driven from the tee with an initial speed of 50.0 m/s and rises to a height of 26.0 m.

(a) Neglect air resistance and determine the kinetic energy of the ball at its highest point.

(b) What is its speed when it is 7.0 m below its highest point?

1 Answer

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  • Anonymous
    1 decade ago
    Favorite Answer

    (a)

    Initially the energy is all kinetic:

    K = 0.047 * 50.0^2 / 2 J

    At height 26.0m, the PE is:

    P = 47.0 * 9.81 * 26.0 J

    The KE at 26.0m is therefore:

    0.047(50.0^2 / 2 - 9.81 * 26.0)

    = 46.8 J.

    (b)

    After a fall of 7.0m, the KE is higher by:

    0.047 * 9.81 * 7.0

    making it

    46.8 + 0.047 * 9.81 * 7.0

    = 50.0 J.

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