Simple Machines

How do levers, pulleys, wheels, and ramps make work easier?

An exploration of how six classic simple machines use mechanical advantage to make difficult tasks easier by trading force for distance.

Check your understanding

1. What is the scientific definition of work?
- A. Cleaning your room or doing homework
- B. Applying a force that makes an object move a distance
- C. Pushing against a wall until you get tired
- D. Building a machine out of metal
2. Which simple machine uses a pivot point called a fulcrum?
- A. A pulley
- B. A screw
- C. A lever
- D. A wedge
3. What is the main way a fixed pulley helps us?
- A. It makes the object weigh less
- B. It changes the direction of our force
- C. It creates extra energy
- D. It makes the rope shorter
4. How are a ramp and a screw related?
- A. They are both types of wedges
- B. They are both types of pulleys
- C. A screw is basically an inclined plane wrapped around a cylinder
- D. They both require a fulcrum to work

1. Why does using a simple machine make a task feel easier?
- A. It reduces the total amount of work needed
- B. It trades distance for force, letting you use less effort
- C. It makes the object you are moving weigh less
- D. It creates energy to do the movement for you
2. If you are using a screwdriver to tighten a screw, what part of the tool acts as the wheel?
- A. The sharp tip
- B. The metal shaft
- C. The wide handle
- D. The screw threads
3. Which of these is an example of a first-class lever?
- A. A wheelbarrow
- B. A pair of scissors
- C. A baseball bat
- D. A set of tweezers
4. What is the main physical difference between using a wagon and dragging a heavy box on the ground?
- A. The wagon creates more friction
- B. The wagon is made of fewer materials
- C. The wagon uses wheels to reduce friction against the ground
- D. The wagon relies on gravity to move

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