So i'm completely lost...here's the problem.(adsbygoogle = window.adsbygoogle || []).push({});

There's a small ball inside an empty sphere. How can I prove this sphere doesn't attract the small ball gravitationally, independently of the position of the ball inside the sphere??

Also, how can I use the result from above to find the gravity force acting on some body of mass (m) inside a planet of radius (R) and mass (M) if this body is at distance r<R from the center of the planet. (The density of the planet is uniform).

Thanks ahead of time.

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# Homework Help: HELP! Gravitational force and spheres. (prob easy)

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