Gravitational strength physics question?

Question

A pendulum clock has a period of 0.690 s on Earth. It is taken to another planet and found to have a period of 0.802 s. The change in the pendulum's length is negligible.

Find the gravitational field strength on the other planet.
____m/s2


I already know that the gravitational strength on the other planet is going to be less than that on earth but i cant figure out what the strength is. Thanx for the help!

Answer 1

The period of a simple pendulum T = 2 pi sqrt ( l / g )
In other words T is proportional to sqrt ( 1 / g )

So T_Earth / T_Planet = sqrt ( g_Planet / g_Earth )