The wheel and axle is one of the six simple machines. Its is characterized by a wheel that rotates around a central point or axle. This simple machine allows a force applied to an object with a large radius to be transferred to an object with a smaller radius, thus increasing the torque. This increase in torque is the mechanical advantage (MA) that the wheel and axle provides. Mechanical advantage is present in each of the simple machines and can be calculated for the wheel and axle.

Make sure that all units of measure are the same.

Find the radius of the larger wheel. In a real-world setting, this value can be obtained by directly measuring with a tape measure or ruler. In a math problem, this value is sometimes given. If it is not, it can be calculated with the formula C=2(pi)(r) by knowing the circumference (C) of the wheel and solving for r.

Find the radius of the axle. This can be achieved by using the same methods as finding the larger radius.

Divide the radius of the large wheel by the radius of the axle to find the mechanical advantage. MA=r(large wheel)/r(axle)

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