Work, Energy and Power Worksheet #1

Do all problems on a separate sheet of paper. Solve problems using the Problem Solving Methodology for homework credit. Work

1. a.) A student lifts a box that weighs 185 N. The box is lifted 0.800 m. How much work does the student do on the box? (Practice Problem 1, Chapter 10)

b.) The student drops the box. How much work does gravity do on the box when it falls 0.800 m?

2. A tugboat pulls a ship with a constant net force of 5.00 x 103 N and causes the ship to move a distance of 3.00 km. How much work is done on the ship?

3. A weight lifter bench lifts a weight of 320 N a distance of 1.70 m. How much work has she done on the weights?

4. A person carries a 218 N suitcase up a flight of stairs. The displacement is 4.20 m vertically and 4.60 m horizontally. a.) How much work does the passenger do on the suitcase? b.) The person carries the same suitcase down the stairs. How much work does the person do on the suitcase now?
c.) Explain the difference between the answers to 4.a and 4.b.

5. A shopper in a supermarket pushes a cart with a force of 36.0 N directed at an angle 25.0° below the horizontal. The horizontal component of the force is 32.6 N. The vertical component of the force is 15.6 N. Find the work done by the shopper on the cart as the shopper moves 50.0 meters along the aisle.

6. A rope is used to pull a box 15.0 m across the floor. The rope is at an angle of 46.0° to the horizontal.