Torque crank and bucket question

[dnt]

Homework Statement

A bucket filled with water has a mass of 70 kg and is attached to a rope that is wound around a 0.035 m radius cylinder. A crank with a turning radius of 0.35 m is attached to the end of the cylinder. What minimum force directed perpendicularly to the crank handle is required to raise the bucket?

Homework Equations

obviously torque = F * r * sin

The Attempt at a Solution

my problem here is i cannot accurately understand the diagram (there is no picture that goes along with it). i cannot tell which r value to use. if someone could clarify that i would appreciate it.

 

[Doc Al]

This is really an equilibrium problem: the bucket (via the rope) exerts a tension on the cylinder tending to make it turn one way; you (via the crank handle) have to exert a torque in the opposite direction to balance it out.

I was able to dig up a diagram that will help you visualize what's going on. Go to http://www.physics.utah.edu/~woolf/2010_rich/rev4.pdf and look at the diagram that accompanies problem #24.