## What is a wedge?

A wedge is simply a triangular tool, often made of metal, wood, stone, or plastic. It is thick on one end and tapers to a thin or sharp edge on the other end. Technically it is an inclined plane (or two inclined planes put together to form a triangle) that moves. A wedge may be attached to a handle to make it easier to use. Good examples of wedges are nails, knives, axes, and your teeth!

A wedge can be used in many ways:

• To cut (knife)
• To split (axe)
• To tighten and to hold back (doorstopper)
• To hold together (nail)

Wedges work by changing direction and force applied to it.
Here is an illustration: Diagram of change in direction and force.

From the above, you will notice that the force applied to the thick end of the wedge overcomes the resistance of the wood. The force is directed downwards, but the wedge directs the force sideways as it drives into the wood.

A wedge may be a single wedge or double wedge. Each does a slightly different job. An axe is a double wedge (see diagram above) and a chisel is a single wedge.