what is the period of oscillation?

Question

A bob of mass m is suspended from a string of length L, forming a pendulum. The period of this pendulum is 2.2 s. If the pendulum bob is replaced with one of mass m and the length of the pendulum is increased to 2L, what is the period of oscillation?

Answer 1

The relation is PREDICTED to be:
T = 2pie (L/g)0.5
where g = 9.8,

This website appears to be very helpful.
http://www.exo.net/~pauld/activities/pendulums/pendulums.html#where

Hope this helps=)