Question

Problem 18

Answer 1

Given information

Given:

In this problem, we must explain why the amplitude of circular waves reduces as they travel away from the source by offering two arguments.

Step-by-step explanation

Step 1.

The energy delivered to the medium by the focus in a circular wave is dispersed along the wavefronts. As a result, the amplitude A of the wave diminishes proportionately to the distance r from the focus as it spreads, as indicated.

 

As the wavefront widens, the energy is dispersed more widely (there is less energy available per unit length of the wave). We know that the square of the amplitude is exactly proportional to the energy.

 

With static water, there is molecular friction, which causes the energy to be absorbed as heat rather than moved. As the numerous molecules pass each other, some of the energy is transformed into heat.