Question

A 6.0-kg object is lifted 1.8 m.

(a) How much work is done against the Earth's gravity?

(b) Repeat if the object is lowered and stayed of the speed is lowered instead of lifted.

Answer 1

(a) $W_1=mgh=6\cdot9.8\cdot1.8=105.84\ (J)$

(b) $W_2=-W_1=-105.84\ (J)$