# A body weighing 4 kg is lifted along an inclined plane of 50 m, applying a force of 0.025N.

**A body weighing 4 kg is lifted along an inclined plane of 50 m, applying a force of 0.025N. What is the efficiency of an inclined plane with a height of 20 m.**

S = 50 m.

g = 9.8 m / s2.

m = 4 kg.

F = 0.025 N.

h = 20 m.

Efficiency -?

The coefficient of efficiency The efficiency is the ratio of the useful work Apol to the spent work Azat, expressed as a percentage: Efficiency = Apol * 100% / Azatr.

Let us express the useful work of Apol by the formula: Apol = m * g * h, where m is the mass of the load, g is the acceleration of gravity, h is the height of rise.

The spent work Azatr will be determined by the formula: Azatr = F * S.

Efficiency = m * g * h * 100% / F * S.

Efficiency = 4 kg * 9.8 m / s2 * 20 m * 100% / 0.025 N * 50 m = 62720%

It can not be so. The efficiency cannot be more than 100%.

Answer: a mistake was made in the problem statement.