Acceleration of gravity , from a pendulum

  • Thread starter th3plan
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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

=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


Staff Emeritus
Science Advisor
Gold Member
Yes, your answer is correct.


Science Advisor
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!)


Staff Emeritus
Science Advisor
Gold Member
In light of HoI's post, I'm assuming that your in S.I. units.
Last edited:
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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