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

To determine the weight of the rod while it is held in equilibrium using a system of pulleys, we need to consider how the forces are distributed throughout the system. In this situation, the force F is provided as 3N, and it is essential to understand the mechanics of the pulley system in relation to the rod.

In a typical arrangement involving a uniform rod and pulleys, the force applied through the pulleys can create a tension that helps balance the weight of the rod. The rod experiences its weight acting downward due to gravity, while the tension in the ropes connected to the pulleys acts upward.

Assuming the pulley system effectively doubles the applied force (which is common in many pulley systems when set up in a way that the load has two supporting ropes), the force F (3N) would be multiplied by two to find the total upwards force acting on the rod. Thus, the total force holding the rod in equilibrium would be 3N × 2 = 6N.

Therefore, given that the rod is in equilibrium, the weight of the rod must equal the total force exerted by the pulleys to maintain that balance. This is why the weight of the rod is calculated to be 6N, making it the