Efficiency is calculated as (useful work output / total energy input) x 100%. In this scenario, the useful work output is 8,000 joules and the total energy input is 10,000 joules. Therefore, efficiency is (8,000 / 10,000) x 100% = 80%.
The answer is 80%.
By using a pulley system, a farmer makes it easier to lift bales of hay by reducing the force needed. The energy she uses to complete the task is 10,000 joules, and the work done on the bales of hay is 8,000 joules. What was her efficiency in this task? (1 point)
Responses
18,000 joules
125%
80%
2,000 joules
1 answer
1 answer