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Wedges

Look at the edges of an axe. What do you see? If you said an inclined plane, you’d be on the right track. Wedges are similar to inclined planes, but there are some differences. An axe is actually two inclined planes put together. An inclined plane and a wedge have completely different purposes.

An inclined plane is generally used to move something from one place to another, e.g., ramps or stairs. Wedges are used to separate objects or to hold objects in place. Confused? Read on for some examples.

 

Fun Facts

  • An axe is a wedge used to chop – or break – logs into pieces.
  • A shovel is a wedge used to break up soil.
  • A knife is a wedge used to cut food or other material.
  • A push pin or tack is a wedge used to hold papers in place.
  • A nail is a wedge used to secure two boards together.
  • A doorstop is a wedge used to hold a door open.

 

Vocabulary

  1. Wedge: a simple machine used to separate or hold together materials
  2. Separate: divide, tear, or move apart
  3. Secure: hold in place; make stable

 

Questions and Answers

Question: Who invented the first wedge?

Answer: We’re not sure, although it seems to have been around for a long time. Arrowheads are a type of wedge. Chisels used for sculpture are also a form of wedge. Early humans probably developed primitive axes to chop wood.

 

Learn More
Visit PBS and Idaho Public Television for a video on simple machines and wedges.