# A slender rod of mass and length is pivoted about a horizontal axis through one end and released from rest at an angle of 30 above the horizontal. The force exerted by the pivot on the rod are the instant when the rod passes through a horizontal position is a) along horizontal b) along vertical c) along a line making an angle of with the horizontal d) along a line making an angle of with the horizontal

## Question ID - 100213 :- A slender rod of mass and length is pivoted about a horizontal axis through one end and released from rest at an angle of 30 above the horizontal. The force exerted by the pivot on the rod are the instant when the rod passes through a horizontal position is a) along horizontal b) along vertical c) along a line making an angle of with the horizontal d) along a line making an angle of with the horizontal

3537

(c)

The angular velocity of the rod about the pivot when it passes through the horizontal position is given by   Radial acceleration of the centre of mass (as centre of mass is moving in a circle of radius is given by Torque about pivot, in the horizontal position, is  Tangential acceleration of the centre of mass, Draw the FBD of the rod at an instant when it passes through the horizontal position. Use Newton’s second law of equation    So, reaction force by the pivot on the rod,  at an angle of with the horizontal

Next Question :

The graph between kinetic energy and momentum of a particle is plotted as shown in fig. The mass of the moving particle is a) 1kg b) 2kg c) 3kg d) 4kg 