A uniform rod is kept vertically on a horizontally smooth surface at a point O. IF it is rotated slightly and released, it falls down on the horizontal surface. The lower end will remain

Options

A. at a distance less than 1/2 from
B. at a distance greater than 1/2 from P
C. at P
D. at a distance 1/2 from P AS.

Answer

D

Explanation

Initially rod is held at rest hence initial velocity of centre of mass of rod is zero. Surface is smooth hence there is no horizontal force on the rod so horizontal acceleration of the centre of mass of rod will remain zero. We can conclude that horizontal displacement of centre of mass of rod will remain zero and thus centre of the rod coincides with the point P as it falls on the floor. Hence distance of the lower end from P will be equal to 1/2. Hence option (d) is correct.