Serway & Jewett — The Laws of Motion: Problem 44

In the situation described in Problem 41 and Figure P5.41, the masses of the rope, spring balance, and pulley are negligible. Nick’s feet are not touching the ground. (a) Assume Nick is momentarily at rest when he stops pulling down on the rope and passes the end of the rope to another child, of weight 440 N, who is standing on the ground next to him. The rope does not break. Describe the ensuing motion. (b) Instead, assume Nick is momentarily at rest when he ties the end of the rope to a strong hook projecting from the tree trunk. Explain why this action can make the rope break.