Wedges

A wedge is a simple machine shaped like a triangle. It has a thick end and a thin pointy end. When you push the thin edge into something, it splits apart. Wedges have been used since ancient times to chop wood and cut things.

How Wedges Work

A wedge is actually two inclined planes stuck together. When force pushes the thick end, the thin edge goes into the object. This turns a downward push into a sideways force. The sharper the wedge, the easier it cuts. Wedges help us do jobs that would be very hard without them.

Wedges We Use

Many tools are wedges. An axe is a big wedge for chopping wood. Knives and scissors have wedge-shaped blades for cutting. Even your front teeth are wedges that help bite food. A door stop is a wedge that keeps doors from closing.

Fun Facts

• Nails are wedges that can push wood apart to make a hole.
• A fork is a wedge that helps stick into food.
• A zipper uses tiny wedges to open and close.

Did You Know?

The sharper a wedge is, the less force you need to use it, which is why knives need to be sharpened.