A uniform thin rod of length 0.80 m and mass 1.5 kg can rotate freely in a horizontal…
PHYSICS · Multi-part · CBSE · Physics · System of Particles and Rotational Motion · System of Particles and Rotational Motion
Problem
A uniform thin rod of length 0.80 m and mass 1.5 kg can rotate freely in a horizontal plane about a vertical axle that passes through one end of the rod and is perpendicular to the rod’s length. The rod is set into rotation and, at a particular instant, it has an angular speed of 10 rad/s.
(a) Determine the rod’s moment of inertia about the given axle.
(b) Calculate the magnitude of the rod’s angular momentum about the axle at the instant described.
(c) At a later time the rod’s angular speed has been reduced to 6.0 rad/s by a small but constant frictional torque exerted by the axle bearing. Compute the magnitude of the change in the rod’s angular momentum during this interval.
(d) Using your result from part (c), determine the magnitude of the average frictional torque exerted on the rod if the reduction in angular speed took 4.0 s.