Question

Where, between the earth and the moon is the gravitation on a mass equal to zero?

Answer 1

which equations to use?

Answer 2

Look up Lagrange points. These are three body problems. The math can get very difficult.

Answer 3

\[F_{\text{earth}}=-G\frac{M_\text{earth}m}{d_\text{earth}^2}\]\[F_{\text{moon}}=-G\frac{M_\text{moon}m}{d_\text{moon}^2}\]
For these forces to be equal \[F_{\text{earth}}=F_{\text{moon}}\]

Answer 4

D= radius

Answer 5

Use UnkleRhaukus equations to determine \(d_{earth}/d_{moon}\), and remember that \(d_{earth}+d_{moon}=D\) , where D is the Earth-Moon distance.

Answer 6

I dont think my math is working here.. could someone describe more?

Answer 7

found the answear; 3.43*10^8m from earth:) thanks everyone!