To mop-clean a floor, a cleaning machine presses a circular mop of radius R vertically down with a
Channel: Doubtnut
Date: 2020-01-03

To mop-clean a floor, a cleaning machine presses a circular mop of radius R vertically down with a total force F and rotates it with a constant angular speed about its axis. If the force F is distributed uniformly over the mop and the floor is `mu`, the torque, applied by the machine on the mop is :