Question

Drew lifts a 50 kg crate onto a truck bed 1 meter high in 2 seconds. Perry lifts 51 kg boxes onto the same truck in a time of 2 minutes. Identify which of the following statements about Drew & Perry is true?

• A. Drew does more work than Perry does.
• B. Perry does more work than Drew does.
• C. They do the same amount of work, but Drew operates at a higher power level.
• D. They do the same amount of work, but Perry operates at a higher power level.
• E. Drew and Perry do the same amount of work and operate at the same power level.

Answer 1

The correct option is C They do the same amount of work, but Drew operates at a higher power level.

Work done against gravity in both the cases=$mgh$ independent of time taken.

However the power at which they operated = Work done per unit time=$\frac{W}{t}=\frac{mgh}{t}$ is different for both the persons.

The lesser the time taken, more would be the power.

Hence Drew operates at higher power.