What is the efficiency of a machine that requires 525 N to lift a 120 kg mass a distance of 5 m while the effort moves 15 m?

To determine the efficiency of the machine, we first need to calculate both the work input and the work output.

The work output is the work done in lifting the mass. It can be calculated using the formula:

Work Output = Force × Distance

The force in this case is the weight of the mass being lifted, which can be calculated as:

Weight = mass × gravity = 120 kg × 9.81 m/s² = 1177.2 N

Therefore, the work output when this mass is lifted 5 m is:

Work Output = 1177.2 N × 5 m = 5886 J (joules).

The work input is the work done by the effort. It is derived from the force applied (525 N) and the distance over which that force is applied (15 m):

Work Input = Effort × Distance = 525 N × 15 m = 7875 J (joules).

Next, we can calculate the efficiency of the machine using the formula:

Efficiency = (Work Output / Work Input) × 100

Substituting in our values:

Efficiency = (5886 J / 7875 J) × 100 ≈ 74.74%

When rounding,