Simple Machines
Simple machines make work easier by changing the direction or magnitude of a force. There are six classic simple machines.
What You Need to Know
Key Concept Diagram
The six simple machines are: lever, wheel and axle, pulley, inclined plane, wedge, screw
Mechanical advantage = Load force ÷ Effort force
A machine multiplies force but not energy — more distance means less force needed
Compound machines combine two or more simple machines
Key Vocabulary
Lever
A rigid bar that rotates around a fixed point (fulcrum)
Fulcrum
The fixed point around which a lever rotates
Mechanical advantage
The factor by which a machine multiplies force
Inclined plane
A flat surface tilted at an angle, used to raise objects
Knowledge Check
Select the correct answer for each question. Click "Check Answer" to see if you are right.
Question 1
A seesaw is an example of which simple machine?
Question 2
A ramp is used to push a heavy box into a truck. This ramp is an example of:
Question 3
If a machine has a mechanical advantage of 4, what does this mean?
Key Concepts Summary
- ●The six simple machines are: lever, wheel and axle, pulley, inclined plane, wedge, screw
- ●Mechanical advantage = Load force ÷ Effort force
- ●A machine multiplies force but not energy — more distance means less force needed
- ●Compound machines combine two or more simple machines