A 1-kg block is lifted vertically 1 m at constant speed by a boy. The work done by the boy is about:

Question

Quizplus · Accepted Answer

The work done by the boy is given by W = Fd, where W is work, F is force, and d is the distance moved in the direction of the force. Since the block is moved at constant speed, the force applied by the boy must be equal and opposite to the force of gravity pulling the block down. The force of gravity on a 1-kg block is approximately 10 N. Therefore, the work done by the boy is W = Fd = 10 N x 1 m = 10 J. Choice C is the only option that comes close to this value.

A 1-Kg Block Is Lifted Vertically 1 M at Constant