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1) During a tug-of-war, team A does 2.20×10 5 J of work in pulling team B 8.00 m. What average force did team A exert? 2) A student librarian lifts a 2.2-kg book from the floor to a height of 1.25 m. He carries the book 8.0 m to the stacks and places the book on a shelf that is 0.35 m above the floor. How much work does he do on the book? 3) A 17.0-kg crate is to be pulled a distance of 20.0 m, requiring 1210 J of work to be done on the crate. The job is done by attaching a rope and pulling with a force of 75.0 N. At what angle is the rope held? 4) An electric motor develops 65 kW of power as it lifts a loaded elevator 17.5 m in 35 s. How much force does the motor exert? 5) A winch designed to be mounted on a truck is advertised as being able to exert a 6.8×10 3-N force and to develop a power of 0.30 kW. How long would it take the truck and the winch to pull an object 15 m? 6) An engine moves a boat through the water at a constant speed of 15 m/s. The engine must exert a force of 6.0 kN to balance the force that the water exerts against the hull. What power does the engine develop? 7) Suppose you are pushing a stalled car. As the car gets going, you need less and less force to keep it going. For the first 15 m, your force decreases at a constant rate from 210.0 N to 40.0 N. How much work did you do on the car? 8) A forklift raises a box 1.2 m and does 7.0 kJ of work on it. What is the mass of the box? 9) An elevator lifts a total mass of 1.1×10 3 kg a distance of 40.0 m in 12.5 s. How much power does the elevator deliver? 10) A 0.180-kg ball falls 2.5 m. How much work does the force of gravity do on the ball?

1) During a tug-of-war, team A does 2.20×10 5 J of work in pulling team B 8.00 m. What average force did team A exert?
2) A student librarian lifts a 2.2-kg book from the floor to a height of 1.25 m. He carries the book 8.0 m to the stacks and places the book on a shelf that is 0.35 m above the floor. How much work does he do on the book?
3) A 17.0-kg crate is to be pulled a distance of 20.0 m, requiring 1210 J of work to be done on the crate. The job is done by attaching a rope and pulling with a force of 75.0 N. At what angle is the rope held?
4) An electric motor develops 65 kW of power as it lifts a loaded elevator 17.5 m in 35 s. How much force does the motor exert?
5) A winch designed to be mounted on a truck is advertised as being able to exert a 6.8×10 3-N force and to develop a power of 0.30 kW. How long would it take the truck and the winch to pull an object 15 m?
6) An engine moves a boat through the water at a constant speed of 15 m/s. The engine must exert a force of 6.0 kN to balance the force that the water exerts against the hull. What power does the engine develop?
7) Suppose you are pushing a stalled car. As the car gets going, you need less and less force to keep it going. For the first 15 m, your force decreases at a constant rate from 210.0 N to 40.0 N. How much work did you do on the car?
8) A forklift raises a box 1.2 m and does 7.0 kJ of work on it. What is the mass of the box?
9) An elevator lifts a total mass of 1.1×10 3 kg a distance of 40.0 m in 12.5 s. How much power does the elevator deliver?
10) A 0.180-kg ball falls 2.5 m. How much work does the force of gravity do on the ball?

Added by Jonathan P.

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