Question

a wrench with an 18 inch handle turns through an angle of 2.3 radians while a force of 50lbs is applied to the end of the handle. find the work done

Answer 1

How do I do this?

Answer 2

Your using a form of work known as torque:
http://upload.wikimedia.org/math/7/5/f/75f97c24e7a50c7ffed8bef0b8348331.png
You can resolve the radius cross product angle using trig:
http://upload.wikimedia.org/math/b/3/7/b37cbcae0e83b25b1f26bbdab44f2e32.png
Substitute the second equation into the first and solve.