# Basic Pendulums Period^2 vs distance

1. Sep 22, 2011

### Saristine

In class we tested the period of different lengths of pendulums. When we squared the period and graphed it against the distance it caused a slope of 3.974 s^2/m. We kept the angles under 15 degrees. We were told that this is close to a constant and asked to figure out what that constant is and what it means, but i can not for the life of me find it in our textbook or on the internet.

--Saristine

2. Sep 22, 2011

### cepheid

Staff Emeritus
I just Googled "period of simple pendulum" and immediately came upon this:

http://en.wikipedia.org/wiki/Pendulum#Period_of_oscillation

Equation 1 tells you everything you need. (By the way, I find it hard to believe this wouldn't have been covered in your class.) What happens if you square both sides of the equation? You end up with something in the form:

T2 = const. * L

What is the constant supposed to be according to the formula? How does this compare to your measured slope?