Question

A wrench with a length of `20 cm` is being used to unscrew a `4/3 cm` bolt. If a torque of `1 Nm` is needed to overcome the friction keeping the bolt in place, what is the minimum torque that must be applied to the wrench to unscrew the bolt?

Answer 1

The torque is the same to screw and to unscrew.

Explanation:

I suppose that you are asking for the perpendicular force applied at the wrench extremity to get a torque of `1`[Nm]. In this case `f` value can e extracted from the equality`f times 0.20=1`. Solving for `f` we obtain `f = 5`[N]