# Acceleration of gravity at pendulum

#### Aamun

1. The problem statement, all variables and given/known data
A pendulum which is 2.00m long makes 84.5 complete oscillations in 4.00 min. What is the acceleration of gravity at that spot? Show all work and formulas.

2. Relevant equations

T=2(3.14) SQRT(l/g)

3. The attempt at a solution

L= g*(T/2pi)^2
2.00=g*(4.00/6.28)^2
g=4.9298 m/s

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I'm not sure if i'm missing a step, or if this is correct.. which is where I run into the problem. I'm also not sure of where the Oscillations would fit in.

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#### nicksauce

Science Advisor
Homework Helper
T is the number of seconds per oscillation. You can figure this out with the data given.

#### Aamun

So it would be 4/84.5= 0.047 minutes per oscillation = 2.84 oscillations per second?

Last edited:

#### nicksauce

Science Advisor
Homework Helper
2.84 seconds per oscillation, yes.

#### cryptoguy

If you're trying to find g, wouldn't it be easier to solve the equation for g immediately? But that's not the main problem. The 4 mins is not T, it is the time it takes for 84.5 oscillations, not 1.

EDIT: lol sorry too late :D

#### Aamun

Ok, I got it, thanks a bunch! =)

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