# wedge

## what is a wedge

A wedge is simple machine that consists of two inclined planes, giving it a thin end and thick end, as you can see in the Figure 1.1. A wedge is used to cut or split apart objects. Force is applied to the thick end of the wedge, and the wedge, in turn, applies force to the object along both of its sloping sides. This force causes the object to split apart. A knife is another example of a wedge. In the Figure 1.2, a knife is being used to chop tough pecans. The job is easy to do with the knife because of the wedge shape of the blade. The very thin edge of the blade easily enters and cuts through the pecans.

## mechanical advantage of a wedge

The mechanical advantage of a simple machine is the factor by which it multiplies the force applied to the machine. It is the ratio of the output force to the input force. A wedge applies more force to the object (output force) than the user applies to the wedge (input force), so the mechanical advantage of a wedge is greater than 1. A longer, thinner wedge has a greater mechanical advantage than a shorter, wider wedge. With all wedges, the trade-off is that the output force is applied over a shorter distance, so force may need to be applied to the wedge repeatedly to push it through the object. Q: Which wedge in the Figure 1.3 do you think would do the same amount of work with less input force? A: The wedge on the left has a greater mechanical advantage, so it would do the same amount of work with less input force.

## instructional diagrams

No diagram descriptions associated with this lesson

## questions

a wedge is a type of compound machine.

``````a. true

-->  b. false
``````

examples of wedges include

``````a) chisels.

b) knives.

-->  d) all of the above
``````

a wedge

``````-->  a) consists of two inclined planes.

b) has two thin ends and a thick center.

c) is used to hold objects together.

d) none of the above
``````

the ratio of output force to input force for a wedge is always less than 1.

``````a. true

-->  b. false
``````

a longer thinner wedge has a greater mechanical advantage than a shorter thicker wedge.

``````-->  a. true

b. false
``````

a wedge with a greater mechanical advantage can do the same amount of work with less input force than a wedge with a lesser mechanical advantage.

``````-->  a. true

b. false
``````

## diagram questions

No diagram questions associated with this lesson