Answer to Question #167791 in Physics for Tithi

Question

Compute the gravitational potential and gravitational field due to a hollow sphere: (i) at a point outside the sphere (ii) at a point inside the hollow space, and (iii) at a point inside the material. 

Answer 1

i)

$$E=\frac{GM}{r^2}, r>R$$

ii)

$$E=0, r<R$$

iii)

$$E=\frac{GM}{R^2}, r=R$$