Physics
ABCDE is a regular pentagon with its centre of gravity at O. What will be the most probable position (W, X, Y, Z or O) of the new centre of gravity:
(a) if a piece of clay is attached at point A?
(b) if the pentagon is cut along the line PQ? (Of the remaining part DCBQPE)
Answer
(a) X
(b) Z
Reason —
(a) If a piece of clay is attached at point A of the pentagon ABCDE then new centre of gravity will be shifted towards A to maintain stable equilibrium and hence, the most probable position will be X.
(b) If the pentagon is cut along the line PQ then only DCBQPE remains which has equal mass distribution on left and right portions about the point O but has greater mass distributed on the upper portion than the lower portion about the point O. So, new centre of gravity will shift towards upper portion i.e. at a point above to the point O to maintain stable equilibrium and hence, the most probable position of new centre of gravity will be Z.
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