Determine the work that needs to be done using the mechanism if its efficiency is 80%

Determine the work that needs to be done using the mechanism if its efficiency is 80%, and the useful work should be 1.2 kJ.

As we know from the school physics course, the efficiency of the mechanism in the general case can be calculated through the ratio of useful work to spent and all this multiplied by 100%.

Let us determine what the work must be equal to, which must be done in order for the useful work to be 1.2 kJ, when it is known from the condition of our problem that the efficiency of our mechanism is 80%:

Azatr = Apol: efficiency * 100%;

Azatr = 1.2: 80% * 100% = 0.015 * 100 = 1.5.

Answer: To do this, you need to do a work of 1.5 kJ.