Question

An object with a mass of `18 kg` is hanging from an axle with a radius of `12 cm`. If the wheel attached to the axle has a radius of `28 cm`, how much force must be applied to the wheel to keep the object from falling?

Answer 1

`75.6 N`

Explanation:

While the body is not falling, total torques applied on the centre of the axle by the weight of the object and the force applied should be zero.

And as torque `tau` is given as `tau = F*r`, we can write:

`"Weight" * 12 cm = "Force"* 28cm`

`"Force"= (18*9.8*12)/28 N = 75.6 N`