Lever- A solid bar that moves up and down on a fixated point called a fulcrum. The different classes of levers are determined on where the fulcrum and load is located and how the effort is being forced. Some examples of a lever is a seesaw, tweezers, or a wheelbarrow. The mechanical advantage formula for a lever is the distance from input force to fulcrum divided by the distance from output force to fulcrum.
Wheel and Axle- Is a machine that is a wheel attached to a shaft or axle. An example is a set of wheels on a bike or skateboard. The mechanical advantage formula for the wheel and axle is the radius of input divided by the radius of output.
Pulley- Is a wheel with a rim that turns on an axle. An example is a wheel with a rope, chain, or cord. There is no specific mechanical advantage formula for the pulley.
Inclined plane- Is a piece of material with a sloping surface like a ramp. An example is like a slide or something used for loading or unloading objects. The mechanical advantage formula is the length of the incline divided by the height of the incline.
Wedge- Is a machine with a thick and thin end. An example of a wedge is a needle or scissors. There is no individual mechanical advantage formula for the wedge.
Screw- Is an inclined plane wrapped around a cylinder. It can be used to raise and lower weights as well as to fasten objects. An example of a screw is the end part on a lightbulb. There is no mechanical advantage formula for the screw.