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Period of a Pendulum

  1. Mar 10, 2008 #1
    A clock pendulum has a period of 1.222 seconds where g = 9.812 m/s^2.

    1. What is the new period of the pendulum when g = 9.797 m/s^2?

    2. How many seconds will a clock using this pendulum lose in 24 hours?

    For the first one, using 7 significant figures, the new period comes out to 1.222935 seconds. I'm not sure how to do the second part. Any suggestions?

  2. jcsd
  3. Mar 10, 2008 #2
    Thanks for the post, but how did you arrive at the resulting numbers? I also don't understand how .102 seconds are lost for every 1 second...
  4. Mar 10, 2008 #3


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    ...start with the equation for period

    [tex]T=2\pi \sqrt{l}{g}[/tex]

    (This has the initial data for T and g)

    What you want is

    [tex]T'=2\pi \sqrt{l}{g'}[/tex]

    and so

    [tex]\frac{T'}{T}= \sqrt{\frac{g}{g'}}[/tex]
    Last edited: Mar 10, 2008
  5. Mar 10, 2008 #4


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    Gold Member

    Whilst we appreciated the help physixguru, how does posting answers help the OP to understand the concept? Would it not be better to guide the student rather than just providing answers? Furthermore, your answers are incorrect.

    I agree with your answer for the first question. As for the second question, how much longer is the period of the pendulum when g=9.797 m/s/s rather than the original value? Therefore, in the time taken for the first pendulum to measure 24 hours, how much time will have passed according to the second?
    Last edited: Mar 10, 2008
  6. Mar 11, 2008 #5
    I duly apologize, but for the clarification it was a typing error. i had copied the wrong data from the question.i respect the rules of the forum and promise to abide by it.This has happened with me the first time .
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