Simple machines are the most basic mechanical devices that apply a force to accomplish something. A complex machine comprises two or more simple machines.
There are six simple machines, and all complex machines are made from these.
You’ll be surprised how often you use a simple machine and how often you come across them throughout the day.
Simple machines help reduce effort or give us the ability to do tasks beyond our standard capabilities.
Six Simple Machines
Lever – is a rigid straight object such as a bar or board that pivots on a turning point that is called a “fulcrum.” The word “leverage” comes from the lever because it makes use of leverage to increase force.
Using a lever involves moving a smaller force a longer distance so that you can lift a load in a shorter distance. An example of a lever is the playground seesaw. Other examples of levers include tweezers and crowbars.
Wheel and Axle – is a wheel with a rod that is attached in the middle as an axle to move loads or help in lifting.
Some wheel and axle machines such as a fishing reel or even a doorknob work like a lever to increase the force. Other wheels and axles such as bicycle wheels are used to move objects.
Pulley is a wheel with a groove in it and a rope that fits into the groove. One end of the pulley system might have a rope is in the groove and the other end of the rope goes around a load. When you pull on the one end the pulley lets you move the load or change the direction of the force.
Examples of pulleys that you might know are window blinds and flag poles. Another type of pulley is used in cars as flat wheels and belts.
Inclined plane is a flat surface that has one end that is higher than the other end. This replaces lifting heavy objects by sliding them up to a higher point. Ramps and slides are examples of included planes.
Wedge is when you place to inclined planes back to back. Wedges are used to push two objects apart. Axes, scissors, and knives are examples of wedges.
Screw – is a special type of inclined plane. It’s an inclined plane that is wrapped around a pole and is used to either hold things apart of to life objects. Jar lids and swivel chairs are types of screws as well as the screws that you use to fix things.
Examples of Simple Machines we use Everyday
Lever – Nutcracker, See Saw, tweezers, stapler, and nail clippers
Wheel and Axle – Wheelbarrow, Bicycles, and a Car
Pulley – Flag pole, Elevators, and Window Blinds
Inclined plane – Ramp, Slides, and Slanted roofs
Wedge – Shovel, Scissors, and Axe
Screw – Jar Lid, a drill, a bolt, and bottle caps
Complex machines for kids
Complex machines comprise two or more simple machines and have advantages over simple machines. They often provide a better solution than just a simple machine alone.
A bicycle is a good example
- Pulley (sprockets and chain)
- Levers (cranks, handlebars, brakes)
How do simple machines make work easier
They make work easier by changing the size of the force direction, or distance the force acts on.
Which simple machines make up scissors
A scissors is a wedge
Simple Machine Facts for Kids:
- Greek philosopher Archimedes discovered the first simple machines.
- Ancient Egyptians used inclined planes instead of ramps building the pyramids.
- Galileo advocated a mathematical theory of how simple machines worked
- A bicycle is a complex machine made up of simple machines.
- It’s believed that the wheel and axle was one of the greatest discoveries that help humans progress. Credit is given to the Sumerians for the first use of the wheel and axle around 5,000 years ago.
What is a simple machine?
The most basic mechanical devices that apply a force to accomplish some form of work
What is a complex machine?
Devices made up of a few of many simple machines
What are the six types of simple machines?
Lever, wheel, and axle, pulley, inclined plane, wedge, screw
Who is given credit for discovering the first simple machines?
Give an example of a complex machine that is made of many simple machines that you might use?
How long ago was the wheel and axle discovered?
Around 5,000 years
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