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## Homework Statement

The earth has a mass of 5.98*10

^{24}Kg and the moon has a mass of 7.35*10

^{22}kg. The distance from the centre of the moon to the centre of the earth is 3.84*10

^{8}m. A rocket with a total mass of 1200 kg is 3.0*10

^{8}m from the centre of the earth and directly in between the earth and the moon. Find the net gravity.

## Homework Equations

F

_{net}= [itex]\frac{Gm1m2}{r^2}[/itex]

## The Attempt at a Solution

The distance from the rocket to the moon is 3.84*10

^{8}-3*10

^{8}= 8.4*10

^{7}

and the rocket to earth is 3.84*10

^{8}m

E<--------R---->M

let right be positive

F

_{net}=F

_{rocket to moon}- F

_{rocket to earth}

F

_{net}=[itex]\frac{G(1200)(7.35*10^2)}{8.4*10^7}[/itex]-[itex]\frac{G(1200)(5.98*10^2)}{3*10^8}[/itex]

F

_{net}=0.83 - 5.3 N

The answer is a negative, so the net force is pulling the rocket towards earth. Knowing this is wrong but what have i done incorrectly?