Simple Machines

What simple machine is used to move objects up or down a slope?

• Inclined plane

• Wheel and axle

• Pulley

• Lever

A librarian lifts a box of books that weighs 93N a distance of 1.5m. How much work does he do?

• 139.5 J

• 1395 J

• 13.95 J

• 1.395 J

What simple machine is used to change the direction of a force applied?

• Inclined plane

• Pulley

• Wedge

• Screw

In a third-class lever, where is the effort located?

• Between the load and the fulcrum

• At the end of the lever

• Between the fulcrum and the load

• At the point of load

If the output force of a wheel is 100N and the input force is 200N, what is the efficiency of the wheel?

• 200%

• 100%

• 50%

• 25%

What is the main benefit of mechanical advantage in machines?

• Increasing the amount of work done

• Reducing the amount of force needed

• Increasing the time taken to do work

• Reducing the efficiency of machines

What is the mechanical advantage for a simple machine?

• The ratio of input force to output force

• The ratio of output force to input force

• The sum of input and output forces

• The difference between input and output forces

The input work done on a pulley system is 450J. What is the efficiency of the pulley system if the output work is 375J?

• 120%

• 82.5%

• 83%

• 375%

How much energy is used by a 75w lightbulb in 15 s?

• 1,215J

• 1,125J

• 5J

• 0.2J

What is an inclined plane?

• A flat surface with a slope

• A vertical surface

• A horizontal surface

• A curved surface