Wave Motion - Mission WM5 Detailed Help


An elastic rope is stretched out and loosely attached to a wall such that its end is free to move. An upward-displaced pulse is introduced into the rope. The pulse travels through the rope, reaches the boundary with the wall and reflects. The reflected pulse will be ____.


 
Fixed and Free End Reflection
When a wave or a pulse traveling through a rope reaches the boundary with a wall, the wave or pulse will reflect and travel back through the same medium towards its origin. The reflection does not cause any alteration in the wavelength, wave speed or frequency of the wave. However, the wave or pulse can become inverted (or flipped) if the end of the rope is attached securely to the wall. Such an end is referred to as a fixed end and causes any upward-displaced pulse to reflect as a downward-displaced pulse. If the end is a free end (not securely tied but allowed to move up and down), the reflected pulse will not be inverted.