Question

A solid disk of mass 500 kg and radius 0.25 m is mounted on frictionless bearings so it can rotate freely around a vertical axis through its center. A cord is wrapped around the rim of the disk and pulled with a force of 10 N, causing the disk to spin. What is the torque exerted on the disk?

1) 2.5 Nm
2) 25 Nm
3) 250 Nm
4) 2500 Nm

Answer 1

The torque exerted on the solid disk when a force of 10 N is applied to a cord wrapped around its rim is 2.5 Nm.

Step-by-step explanation:

The question involves calculating the torque exerted on a disk when a force is applied to a cord wrapped around its rim. In physics, torque (τ) is calculated using the equation τ = rFsin(θ), where r is the radius of the disk, F is the force applied, and θ is the angle between the force and the radius. Given that the cord is pulled perpendicularly to the radius (which means θ = 90° or sin(θ) = 1), the torque can be simplified to τ = rF. For a solid disk of mass 500 kg and radius 0.25 m with a force of 10 N applied to the rim, the torque is calculated as τ = 0.25 m * 10 N = 2.5 Nm.