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Homework Help: Acceleration of gravity , from a pendulum

  1. Apr 9, 2008 #1
    1. The problem statement, all variables and given/known data

    A space explorer lands on a new plant, and he wants to determin the gravity on it. He makes a pendulum with a lengh of 800 mm and he observes it does 24 full swings in 1min and 20 seconds. What is the acceleration of gravity to be from this ?



    3. The attempt at a solution

    period
    =2pie multiplied by square root of (lenth of the pendulum over gravity.

    period= 80/24=3.333333. gravity = 2.8

    Is this right what i did, any help would be great
     
  2. jcsd
  3. Apr 9, 2008 #2

    Hootenanny

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    Yes, your answer is correct.
     
  4. Apr 9, 2008 #3

    HallsofIvy

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    Well, you are going to have to explain more exactly what you did.

    You have determined that [itex]2\pi \sqrt{800/g}= 10/3[/itex]. Now, exactly how did you solve that equation for g? Also, what units is your answer in? I hate to disagree with Hootenanny but your answer makes no sense until you say what the units are.

    (That's not true- I love to disagree with Hootenanny!)
     
  5. Apr 9, 2008 #4

    Hootenanny

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    In light of HoI's post, I'm assuming that your in S.I. units.
     
    Last edited: Apr 9, 2008
  6. Apr 9, 2008 #5
    well i use equation T=2pi sqrt( L/g) =T and T is 10/3, so i solved for g, since i know the Lengh is 801m, then i got it to meters
     
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