Posted by Andrea on .
A 2.1kg brass ball is transported to the Moon.
a)What is the mass of the brass ball on the earth and on the moon?
Wouldn't it be 2.1kg for the earth as well as for the moon?
b)Determing the weight of thee brass ball on the earth.
F_g=(G*m_ball*m_earth)/r^2
=20.58N
c) the weight on the moon.
G_g=m*g_moon
What is the gravitational acceleration on the moon? Also is this equation acceptable or would I have to use the equation I gave in part b)?
Thanks for your help.

Physics 
Michael,
a) Yes, mass is constant regardless of location.
b) Weight = Mass * Gravity
Weight = 2.1kg * 9.8 m/s^2
Weight = 20.58N
There are three, so 61.74 N is the answer.
c) Gravity on the moon is about 1/6 that of the earth. It is 1.6 m/s^2.
Weight = Mass * Gravity
Weight = 2.1kg * 1.6 m/s^2
Weight = 3.36N