Q: The centre of gravity of a system of rigid bodies coincides with their centre of mass if and only if
(a)their centre of mass is at their geometrical centre
(b)the acceleration due to gravity is same throughout the system of bodies
(c)the rigid bodies have same uniform mass densities
(d)the rigid bodies are very large
Correct Answer: (b)
The correct answer is (b) 'the acceleration due to gravity is same throughout the system of bodies'. This question from the Science & Technology domain tests knowledge of Physics.