The centre of mass of an extended body on the surface of the earth and its centre of gravity

Options

A. are always at the same point for any size of the body
B. are always at the same point only for spherical bodies.
C. can never be at the same point
D. both can change if the object is taken deep inside the earth

Answer

D

Explanation

For small objects, say, of sizes less than 100 m, centre of mass is very close to the centre of gravity of the body. But when the size of object increases, its CM and CG become far from each other. Also, if an object is taken far away into the space, away from the earth, both CG and CM will change but when the object is taken deep inside the earth, CM and CG will hardly change.
The correct option is (d).