Engineering: Simple Machines

We use machines to make work easier and to get things done faster. A simple machine has few or no moving parts. This lesson will introduce you to six types of simple machines and is a great guide for engineers.  Engineers use these machines to make the world a better place. These simple machines have helped humans to build things for centuries. Ancient Egyptians used simple machines, like the inclined plane, to build the pyramids. Simple machines used in engineering let us solve everyday challenges.

After this lesson, you will learn:

  • What a simple machine is and how it could be used in engineering
  • What the six types of simple machines are
  • How ancient engineers used simple machines

A List of Simple Machines

If you hear the word “work” in physics class, this refers to the amount of force used to move an object. Simple machines help us move objects with less work, and that helps us save energy. All of the machines listed help move objects in different ways.

Wedge: A wedge forces two objects apart. A wedge works by applying force to a large area of its surface. That force is directed toward a smaller area, which then drives objects apart. You have seen many wedges in real life. Nails and axes are both examples of wedges.

Wheel and Axle: The wheel and axle reduces friction when moving an object. This means the object can be moved with less force. The wheel turns around the axle, and this rolling motion causes an object to move. You can spot wheels and axles all over the place, like on a car, wheelbarrow, bike, or rollerskates.

Lever: There are three parts to how a lever works: the load, fulcrum, and force. The load is the object you are lifting. The force is applied at the point of contact, and the fulcrum directs the energy. When you push on a crowbar, you are applying force to a lever. Seesaws, fishing poles, and bottle openers also have levers.

Inclined Plane: An inclined plane is something that works like a ramp. It’s used to lift objects to a greater height. Inclined planes don’t need much force, but it must be applied over a greater distance. Highways, stairs, and conveyor belts all use inclined planes.

Screw: Screws can lift objects or hold things together. They are basically an inclined plane wrapped around a shaft. The threads of the screw grip material and hold it tight. They can be tightened or removed by winding and unwinding. Find screws on bolts, clamps, and jar lids.

Pulley: A pulley is a grooved wheel and a rope used to change the direction of a force. By pulling down on the rope, gravity is used to lift an object up. Pulleys are used on flag poles, clotheslines, and sails.

Compound Machines: Compound machines are a combination of two or more simple machines. A can opener has a wedge and lever, and so does a shovel.

Vocabulary Terms

Design: To create a well-thought-out plan, often in a graphic form

Engineering: Applying math and scientific principles to design and manufacture, economic structures, machines, and processes

Force: Pushing or pulling on an object

Inclined plane: A slanted surface that raises objects to a greater height

Lever: A bar on a fixed point that increases or decreases force to lift an object

Mechanical advantage: Simple machines are used to accomplish more work with less force and effort

Pulley: A machine that lifts a load by changing the direction of a force

Pyramid: Ancient structures built in Egypt and Mesoamerica with triangular bases and four triangular sides that meet at a point

Screw: A rod with a spiral thread that holds materials together

Simple machine: A machine with few or no moving parts that makes work easier

Spiral: A curve that winds around a fixed point

Tool: A device used to make work faster and easier

Wedge: A machine with a thick end and a thin end used for tightening, splitting, and securing

Wheel and axle: A disc that turns around a supporting cylinder at its center

Work: Force multiplied by travel distance (W= F x d)

Simple Machine Activities

Stack it Up!: You can use math to design your own pyramid! You’ll even figure out how many blocks you need in your base.

Action Figure: Create a puppet that jumps and dances using levers and strings.

Simple Machine Challenge: Learn more about all the simple machines mentioned above in these fun lesson plans.

Closing Questions

Can you name the six simple machines?

How do simple machines make work easier?

Why are simple machines used in engineering?