Homework Statement
An old, heavy wooden door leads to a basement storm cellar. If it requires 400N to lift the door by its handle and swing it open, what is the Weight (in N) of the door itself? (Also, there is a picture that shows from the hinge to the handle is 1.6m)
Homework Equations...
The unit of energy is just Joules.. Right? Well in this case.
So would it just be a potential energy of .02J since the total work done is calculated by the Newtons of force and meters which they don't give in the problem?
Homework Statement
A person does .02 Joules of work winding a watch. Assuming NO loss of energy to friction, how much energy is stored in the watch's main spring?Homework Equations
PE=1/2kx^2 ?? I have no idea..The Attempt at a Solution
I've gotten nowhere trying to do this problem without...