| A | B |
|---|
| Compound Gear | two or more gears that are attached to the same shaft. |
| Driver | the input gear in a gear train, usually connected to a power source. |
| Energy | the ability to do work or cause change. |
| Follower | the output gear in a gear train. |
| Gear | a wheel with teeth that meshes together with other gears. |
| Gear Ratio | the ratio of the number of teeth of the follower to the number of teeth of the driver. |
| Gear Train | a series of gears that transmits power from one shaft to another. |
| Gearing Down | a gear ratio that that results in the follower turning slower than the driver. |
| Gearing Up | a gear ratio that that results in the follower turning faster than the driver. |
| Idler | a gear between the driver and the follower. |
| Mechanical advantage | the ratio of output force to the input force applied to a mechanism. |
| Power | the rate at which work is done. |
| Rotational Speed | the velocity at which an object rotates (RPM). |
| Torque | a twisting force that can cause rotation. |
| Work | force exerted on an object that causes the object to move some distance. |
