Question

The magnitude of gravitational field at distance r1 and r2 from the centre of a uniform sphere of radius R and mass M are F1 and F2 . If r1>R and r2

Answer 1

Answer:

 When r1>R and r2>R i.e., the points are outside the sphere in this case, the gravitational field is given by GM/r2.

So, F1=r12GM and F2=r22GM

F2F1=r12r22 i.e., option (b) is correct.

(ii) When r1<R and r2<R, i.e., the points are inside the sphere within the sphere of radius

Now, M1=34πr3ρ

F1=G.34πr13ρ/r12

F2=G.34πr23ρ/r22

F2F1