Question

A wave is traveling from one medium to another. If the wave is partially transmitted and partially reflected from the boundary, what will happen to the amplitude of the reflected wave?

Answer 1

This is a conservation of energy question. A wave has a specific amount of energy. If when a wave strikes a surface and is divided such that part of the wave is reflected and part is transmitted, according to the conservation of energy will the reflected wave have more, the same, or less energy than it had before striking the surface? Note that energy is proportional to the square of the amplitude:\[E∝A ^{2}\]