# Glencoe Science Level Blue

## Chapter 20: Work and Simple Machines

### Standardized Test Practice

 1 What is the work done by a boy if he expends 40.5 W of power pulling a sled up a hill in 10.5 s? A) 3.9 J B) 39 J C) 425 J D) 42.5 J 2 What is the output force of the lever if the input force is 300 N? (2.0K) A) 30 N B) 200 N C) 1800 N D) 50 N 3 If the input force is 110 N, how far should the triangular block be placed from the input force edge of the plank so that the output force is 44 N? (2.0K) A) 35 cm B) 44 cm C) 56 cm D) 40 cm 4 What is the input force needed to lift a 30-N weight using the pulley system in the illustration? (3.0K) A) 5 N B) 15 N C) 20 N D) 10 N 5 What work have you done if you push a wagon with a force of 36 N for a distance of 2.0 m, and the wagon continues to roll for 1.0 m after you stop pushing? A) 12 J B) 18 J C) 72 J D) 110 J 6 What is the mechanical advantage of a wheel with a radius of 6.0 cm connected to an axle with a radius of 1.1 cm? A) 0.18 B) 1.1 C) 6.6 D) 5.5 7 How far do you have to push a 5.5-kg box to do 38 J of work if you use a force of 22 N? A) 0.3 m B) 1.7 m C) 3.2 m D) 9.5 m 8 A fulcrum is used for which simple machine? A) inclined plane B) pulley C) wheel and axle D) lever 9 What is the mechanical advantage of an inclined plane if its height is 5.0 m, the sloped surface is 12.0 m long, and its horizontal distance is 7.0 m? A) 1.4 B) 2.4 C) 1.7 D) 2.1 10 What is the efficiency of a ramp if you do 175 J of work pushing a 12-kg box up the ramp, and the ramp does 125 J of work? A) 59% B) 71% C) 68% D) 85%