Raising a load of 100 N uniformly with the help of a movable block, the worker applies

Raising a load of 100 N uniformly with the help of a movable block, the worker applies a force of 70N, which is the efficiency of this block.

To calculate the efficiency of the used mobile unit, we apply the formula: η = Ap / Az = P * h / (F * S) = P * h / (F * 2h) = P / (F * 2).

Values of variables: P – weight of the lifted load (P = 100 N); F is the applied labor force (F = 70 N).

Let’s make a calculation: η = P / (F * 2) = 100 / (70 * 2) = 0.714 (71.4%).

Answer: The used mobile unit has an efficiency of 71.4%.