To move a mass of 2.5 kg on the end of a lever that pivots 3 m from one end, what force is needed?

To determine the force required to move a mass at the end of a lever, we can utilize the principle of torque. Torque (τ) is calculated as the product of the force (F) applied and the distance (d) from the pivot point to the point where the force is applied. This relationship can be expressed using the formula:

τ = F × d

In this scenario, the mass at the end of the lever is 2.5 kg and it is positioned 3 meters from the pivot point. The weight of the mass can be calculated using the formula:

Weight (W) = mass (m) × gravitational acceleration (g)

Here, gravitational acceleration (g) is approximately 9.81 m/s². Therefore, the weight of the mass is:

W = 2.5 kg × 9.81 m/s² = 24.525 N

The torque created by this weight acts at a distance of 3 m from the pivot point:

τ = W × d = 24.525 N × 3 m = 73.575 N·m

To find the force needed to create the same amount of torque when applied at the same distance of 3 m, we set up the equation