A simple machine is a device that reduces the force required to move or deform an object. This is accomplished by increasing the distance over which the effort, or driving force, must be applied.
A truck ramp and a hammer are examples of simple machines.
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The truck ramp reduces the force required to lift boxes onto the truck. With a ramp, the boxes have to be moved over a longer distance.
Source: Rozhkov Denis, Shutterstock.com
The hammer makes it easier to remove the nail, but requires a greater movement of the hand to do so.
There are 6 types of simple machines, often grouped into two families: inclined planes and levers.
An inclined plane is a flat surface placed at an angle.
This family includes the inclined plane but also the screw and the wedge, which are simple machines whose operation is similar to that of the inclined plane.
A lever is a simple machine composed of a rigid part that rotates around a fixed point, called the fulcrum or pivot.
This family includes the lever but also the wheel and the pulley, which are simple machines whose operation is similar to that of the lever.
A complex machine is an assembly of simple machines. A wheelbarrow is an example of a complex machine, since it combines a lever and a wheel.
