# Pendulum Period

## Homework Statement

Prove the equation: T = 2 pi * sqrt(L/g), then determine the period of a "seconds pendulum" (period = 2 sec on Earth) on the surface of the moon.

T = 2pi * r/v
T = 2pi/ω
ar = rω2

## The Attempt at a Solution

Do you assume ar is ag?

T = 2pi/ω
= 2 * pi / sqrt(a/r)
= 2 * pi * sqrt(r/a)

...Apparently, L is supposed to be the length of the pendulum, so somewhere along the line, I completely screwed up.

I can solve the second part of the question just fine, but since I've never actually seen T = 2 pi * sqrt(L/g) used or proved, I'd rather not work with it until I understand where it comes from and how it works.