Which statement about gears is correct?

Which statement about gears is correct?

• A. Gears convert electrical energy to heat.
• B. Gears transmit rotational motion and torque.
• C. Gears primarily cool mechanical systems.
• D. Gears regulate electrical circuits.

Answer: (B)

Gears are designed to transfer rotational motion and force from one shaft to another. When gears mesh, the teeth enforce a fixed speed relationship between the connected shafts, so a gear with more teeth will drive the other at a slower speed but with higher torque, while the reverse gear arrangement does the opposite. The overall power transfer follows the balance of input and output: input torque times input speed roughly equals output torque times output speed (minus small losses from efficiency). Gears can also change the direction of rotation depending on how they’re arranged. They aren’t used to convert electrical energy to heat, cool systems, or regulate electrical circuits, which are outside their mechanical purpose.

Gears are designed to transfer rotational motion and force from one shaft to another. When gears mesh, the teeth enforce a fixed speed relationship between the connected shafts, so a gear with more teeth will drive the other at a slower speed but with higher torque, while the reverse gear arrangement does the opposite. The overall power transfer follows the balance of input and output: input torque times input speed roughly equals output torque times output speed (minus small losses from efficiency). Gears can also change the direction of rotation depending on how they’re arranged. They aren’t used to convert electrical energy to heat, cool systems, or regulate electrical circuits, which are outside their mechanical purpose.