Question
Explain the term ‘centre of gravity’ of a body.

Answer

A body can be considered to be made up of a number of particles, each particle has weight ‘W’. Weight of all these particles acts vertically downward and can be replaced by a single resultant force. This force passes through a fixed point. ‘G’ which is a point where the algebraic sum of moments of weight of all the particles is zero and is called the centre of gravity of the body.
Thus we can define ‘CG’ as ‘the point through which the weight of the body acts irrespective of the position of the body.’

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