A machine takes in 500 joules of energy and produces 350 joules of useful work, the rest lost as heat. What is its mechanical efficiency?
Pick an answer
Correct!
Not quite. The correct answer is highlighted.
Correct answer to question 125 (Mechanical Comprehension): 70 percent
Method
Efficiency is useful output divided by total input: 350 / 500 = 0.70, or 70 percent.
Updated: November 2026
Raise your AFQT scoreFree for iPhone and Android
