A team of students builds a lever as a science project. They expend 10,300 Joules of energy to lift some bricks with the lever If 6,283 Joules of energy are applied to the bricks, what is the lever's efficiency? (1 point)
A) 39%
B) 164%
C) 0.61%
D) 61%
To calculate the lever's efficiency, we need to use the equation:
Efficiency = (Useful energy output / Total energy input) x 100%
Useful energy output is the energy used to lift the bricks, which is 6,283 Joules. Total energy input is the energy expended to lift the bricks, which is 10,300 Joules.
Efficiency = (6283 / 10300) x 100%
Efficiency = 0.61 x 100%
Efficiency = 61%
Therefore, the lever's efficiency is 61%, which corresponds to option D.