How does a hammer used to pull a nail from a board change the direction of the force?

HELP PLEASE I NEED THIS BY TOMORROWHow does a hammer used to pull a nail from a board change the direction of the force?
The hammer's claw is like a lever. Since the claw is much longer from the fulcrum point than the hammer side, it produces more force. When you stick the claw to the nail, you apply a force of downwards. Then as you turn the hammer or pull it down, it pulls the nail going upwards. Like a lever, or see-saw.How does a hammer used to pull a nail from a board change the direction of the force?
Like jcvcvc said what the hammer does is supply you with a fulcrum, such that pulling the handle, the force made to pull out the nail will be multiplied. See if you can understand it from





http://en.wikipedia.org/wiki/Lever





The Hammer is listed there as a Lever of the first kind at #6.
The curved hammer head changes the force direction. Also, the direction changes as the nail is extracted, so the geometry of the nail, the surface and the hammer changes.
lever