# Gravitational constant problem

1. Nov 8, 2013

### Eagle's Wings

1. The problem statement, all variables and given/known data

Titania, the largest moon of the planet Uranus, has 1/8 the radius of the earth and 1/1700 the mass of the earth. a) What is the acceleration due to gravity at the surface of Titania? b) What is the average density of Titania?

2. Relevant equations

F$_{g}$ = $\frac{Gm_{E}m}{r^{2}}$
F$_{g}$ = ma

3. The attempt at a solution

I haven't looked at part b) yet because I use the above equations and I get 4.99E8 m/s^2, but the real answer is 0.37 m/s^2...not sure what I'm doing wrong. Am I even using the right equations?

Last edited: Nov 8, 2013
2. Nov 8, 2013

### Eagle's Wings

wait, never mind. it is asking for the gravity on that moon so I just use the same equation used to find gravity on the earth. Answer to my own question: yes, yes you are using the wrong equations.