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

The formula used for calculating the velocity of cogwheels relates to the rotational speeds and diameters of the gears in a system. The correct choice illustrates the relationship between the number of teeth (or turns) and the circumferences of the cogwheels. In mechanical systems, when one cogwheel drives another, the speed and torque are inversely related to the number of teeth or the diameter of the cogwheels.

The formula \(N1 \times V1 = N2 \times V2\) indicates that the product of the number of teeth (N) on the first wheel and its rotational velocity (V) is equal to the product of the number of teeth on the second wheel and its rotational velocity. This relationship ensures that if one wheel spins faster (higher velocity), the other wheel must have fewer teeth to maintain a mechanical balance, hence the inverse relationship between speed and the number of teeth.

In contrast, the other options do not express a relationship that accurately captures the dynamics of cogwheel interactions. The addition and subtraction denoted in the other choices do not apply to rotational motion in cogwheels and would not yield a meaningful or accurate understanding of the mechanical principles involved. The correct formula is fundamental in gear systems, allowing engineers to