Bennett Mechanical Comprehension Practice Test

When gears are meshed together, they rotate in opposite directions due to the nature of how the gear teeth interlock. Each tooth of one gear pushes against the tooth of the adjacent gear in a way that causes the first gear to rotate in one direction while simultaneously forcing the second gear to rotate in the opposite direction. This fundamental mechanical principle ensures that any two gears that are directly engaged will always rotate in contrasting directions. For instance, if you have a gear turning clockwise, the gear that is directly connected to it will turn counterclockwise. This alternating pattern is critical for the operation of various mechanical systems, ensuring coordinated movement between different parts. The other options are not valid in this context. The first option suggests that gears turn in the same direction, which contradicts the interlocking mechanism of gears. The second option states that they do not rotate, which is incorrect, as engagement of the teeth necessitates movement. Finally, the fourth option implies that the direction of rotation depends on gear size; however, the size of the gears does not change the fundamental rule that they will always rotate in opposite directions when meshed directly.