The frictional torque exerted on the platform by the axle as the platform rotates will be;
Torque is the force's twisting action about the axis of rotation. Torque is the term used to describe the instant of force. It is the rotational equivalent of force. Torque is a force that acts in a turn or twist.
The amount of torque is equal to force multiplied by the perpendicular distance between the point of application of force and the axis of rotation.
Work done by the frictional torque = Change in the rotational kinetic energy of the wheel
Where,
is the frictional torque
is the final angular velocity
is the initial angular velocity
is the angular displacement
Hence, the frictional torque exerted on the platform by the axle as the platform rotates will be;
To learn more about the torque, refer to the link;
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