일반물리학 1 — Potential Energy and Conservation of Energy: Problem 37

37 At a lunar base, a uniform chain hangs over the edge of a horizontal platform. A machine does 1.0 J of work in pulling the rest of the chain onto the platform. The chain has a mass of 2.0 kg and a length of 3.0 m. What length was initially hanging over the edge? On the Moon, the gravitational acceleration is 1/6 of 9.8 m/s².