Finding g from a 2.00 m pendulum making 84.5 oscillations in 4 minutes

[ahrog]

Homework Statement

A pendulum with is 2.00 m long makes 84.5 complete oscillations in 4.00 minutes. What is the acceleration of gravity at that spot?

Homework Equations

TG=(4pi^2/T^2)L

The Attempt at a Solution

g=(4pi^2/240s^2)2.00m
g= 0.0013707...

Which doesn't make sense, and it seems way to simple to be getting 8 marks for it. What am I missing?

 

[rl.bhat]

Find the time for one oscillation.

 

[Nabeshin]

In your solution you seem to have just put in 240s for the period. This would certainly be true if the pendulum completed one oscillation in four minutes...

 

[ahrog]

Oh geez *smacks head* Such an easy solution. Thanks!