A wedge is one of the six simple machines. It is characterized by an object that has a defined width at one side that slopes to a point at the other end. This simple machines allows a force that is applied over a large area to be concentrated upon an edge or smaller area, such as a knife. This concentration of force is the mechanical advantage (MA) the wedge provides. Each of the six simple machines offers a mechanical advantage, and it can be quickly calculated for a wedge.
Make sure that all lengths are in the same unit of measure.
Find the length of the sloped surface of the wedge. For a real-world object, this can be found in by measuring with a tape measure or ruler. In the case of a math problem, this value is sometimes given. If it is not, it can be calculated using the Pythagorean Theorem (a^2)+(b^2)=(c^2) or the law of cosines (cos(a)/A)=(cos(b)/B)=(cos(c)/C)
Find the width of the large end of the wedge. This too can be found either by direct measurement or by mathematical calculation.
Divide the slope length by the width of the wedge to find the mechanical advantage. MA=(Slope Length)/(Width)
- knife image by Horticulture from Fotolia.com