Calculate force for torque by specifying a required velocity

I am able to calculate a force using a required velocity and apply this to a Rigidbody using AddForce. After a lot of investigation, I stumbled across the answer in Unity’s forums, here is the working equation:

Force = (speed / 2) * mass

I now want to do something similar to rotate a Rigidbody using AddTorque. Nothing I’ve come across comes close to this method. Please help.

P.S. It is important that I calculate the force required, which eliminates using ForceMode.Acceleration.

The solution to my problem seems too simple but it works…

Force = Speed / Time.fixedDeltaTime

i.e. A rotation speed of 1.5 required a force of 75.