Bennett Mechanical Comprehension Practice Test 2025 - Free Practice Questions and Review Guide

The main purpose of gears in a machine is to transmit torque and motion between different parts. They can be used to change the direction of force, increase or decrease speed, or provide mechanical advantage. When gears mesh together, they work by converting rotational motion into different outputs.

The correct answer focuses on the role of gears in facilitating the efficient transfer of motion and force. While gears indeed can influence friction within a machine, their primary function is not to increase friction but rather to engage in a controlled, precise manner that aids in the overall operation of the machine.

In many applications, gears are designed to ensure smooth and controlled interactions between components, thus improving the machine's efficiency. Although increasing friction might prevent slipping in some mechanical systems, it is not the main function of gears. Rather, the function is to ensure that the rotational movement is directed and modified appropriately to meet the mechanical needs of the system.