As a ball falls freely toward the ground, its total <span>mechanical energy "remains the same" but it should be noted that its potential energy is decreases at this time. </span>
The effiency of a machine is
(output work or energy) / (input work or energy) .
For the system described in the question, that's
(123 J) / (150 J) = 0.82 = 82% .
Answer:
I think the Answer is B. Longitudinal waves
