The mechanical advantage (amount of change in speed or torque) of connected gears is proportional to the **number of teeth** each gear has. Called gear ratio, it's the ratio of the number of teeth on the larger gear to the number of teeth on the smaller gear. For example, a gear with 12 teeth connected to a gear with 9 teeth would have a gear ratio of 4:3.

If you have a gear train with two gears, the first with 32 teeth and the second with 12 teeth, how many revolutions does the second gear make for each revolution of the first gear?

4.2 | |

5.7 | |

2.7 | |

0.9 |