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Homework Help: Pendulum on the moon

  1. Dec 8, 2005 #1
    A pendulum consists of a mass m = 0.070 kg hanging from a flexible string of length L. The string is very thin, very light, and doesn't stretch much. It makes small oscillations, with a period of 0.704 s. Find the oscillation frequency of the pendulum. Neglect any air resistance.
    I got this part ok.. the answer was 1.42 Hz.
    The next part says.. Find the period of the same pendulum on the moon's surface. The gravitational acceleration of the moon is 1.67 m/s^2.
    I used the equation
    [tex] T= 2\pi \sqrt L/g [/tex]
    [tex] .704 = 2\pi \sqrt L/9.8 [/tex]
    Solving for L gave me 12.1 m
    I then used this equation for the period on the moon
    [tex] T= 2\pi \sqrt 12.1/1.67 [/tex]
    T= 16.9 s, which wasn't right.
    Can someone help? Thanks.
  2. jcsd
  3. Dec 8, 2005 #2


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    Homework Helper

    The length is wrong.
    I get about 12.3 cm

    Remember, the g-value is under the square-root sign
  4. Dec 8, 2005 #3
    Ok I got it.. thanks!
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