Chapter 14.7, Problem 14.6GI

You’re holding one end of a taut rope, and you can’t see the other end. You tweak the rope to give it an upward displacement, sending a pulse down the rope. A while later, a pulse comes back toward you. Its displacement is upward, but with considerably lower amplitude than the initial displacement you provided. Assuming there’s no energy loss in the rope itself, you can conclude that the far end of the rope is (a) attached to a rigid anchor point, (b) attached in such a way that it’s free to slide up and down, (c) tied to another rope with less mass per unit length, or (d) tied to another rope with more mass per unit length.