1. WHAT IS WORK?

2. Work when you exert a force on an object that causes the object to move some distance Work is done when the object moves in the same direction as the force Is work being done? Carrying books to school Lifting a box onto a table Pushing up against a wall

3. C ALCULATING WORK Work = Force x Distance Joule unit used to measure work When do you do more work? Lifting a 50N box onto a table OR Lifting a 100N box onto the same table

4. C ALCULATING W ORK When do you do more work? Pushing cart up a 20m ramp OR Pushing the same cart up a 50m ramp Practice How much work do you do lifting a 25N text book.75m from the floor to your desk?

5. P OWER Power is the rate at which work is done the amount of work done on an object in a unit of time Power = Work Time Watt unit used to measure power

6. P RACTICE A motor exerts a force of 12,000N to lift and elevator 8.0m in 6.0 seconds. What is the power of the motor? A crane lifts an 8,000N beam 75m to the top of a building in 30 seconds. What is the crane’s power?