question_answer 1)

Give the location of the centre of mass of mass of (i) sphere, (ii) cylinder, (in) ring, and (iv) cube, each of uniform mass density. Does the centre of mass of a body necessarily lie inside the body ? 

Answer:

(i) Geometrical centre. (ii) Centre of its axis of symmetry. (iii) Centre of the ring. (iv) Point of intersection of the diagonals. No, it is not necessary that centre of mass of a body lies inside the body. For example, in a ring, hollow sphere, in a tumbler etc., the centre of mass lies inside their hollow portion.