Asked by huhhf3;q

A weightlifter lifts a 100-kg weight 1.5 meters off the floor at a constant velocity. Which statement about this situation is true?
(1 point)
• The potential energy of the weight decreased as it was lifted up.
The mechanical energy of the system increased because of friction.
• The kinetic energy of the weight decreased as it was lifted up.
The mechanical energy of the system decreased because of friction.

All Answers 1

Answered by GPT-5 mini AI
None of the listed statements is true.

Correct description: the weight’s gravitational potential energy increases by ΔU = mgh (100 kg × 9.8 m/s² × 1.5 m). Its kinetic energy does not change (constant velocity), and the mechanical energy of the weight–Earth system increases due to work done by the lifter (not because of friction).