# With the help of a simple mechanism, work A1 was performed and the total work was equal to A2.

**With the help of a simple mechanism, work A1 was performed and the total work was equal to A2. Which of the following statements determines the efficiency of the mechanism a) A1 + A2 b) A1 / A2 c) A2 \ A1**

Based on the condition of the problem, A1 is the work expended by the mechanism, taking into account its efficiency, and A2 is the useful mechanical work, calculated by the formula A = F × S

The efficiency of the mechanism required in the problem is determined by the ratio of useful work to the work expended, that is, the formula for calculating it will look like this: efficiency = A useful / A spent (and × 100 if the efficiency is required to be expressed as a percentage)

Considering the above, we substitute the data from the condition into the formula: efficiency = A2 / A1

The correct answer is “с”.