1. POWER: What is it?

2. How hard are you really working?
Power = the rate of doing work
To increase power:
Increase the amount of work done in a given time
Do a given amount of work in less time

3. Work and Power Video

4. Formula for Power W
Joules P
Watt T
seconds

5. Does your backpack make you stronger?
Set your backpack on the ground. Lift the backpack up to the table and place it on the table. Calculate your power used. Critical Thinking: What all do we need to measure to determine the power?

6. Solve the Problem
Your family is moving to a new apartment. While lifting a box 1.5 m straight up to put it on the truck, you exert an upward force of 200 N for 1.0 seconds. How much power is required to do this?

7. Solve the Problem
You lift a book from the floor to a bookshelf 1.0 meter above the ground. How much power is used if the upward force is 15.0 N and you do the work in 2.0 seconds?

8. Solve the Problem
You apply a horizontal force of 10.0 N to pull a wheeled suitcase at a constant speed of 0.5 m/s across flat ground. How much power is used?