Chapter 11, Problem 20Q

To determine

When a standing wave exists on a string, the vibrations of incident and reflected waves cancel at the nodes. Does itmean that energy was destroyed?

Answer to Problem 20Q

Solution:

No.Energy is neither created nor destroyed. The reflected waves simply cancel the vibration out through destructive interference at nodes.

Explanation of Solution

No. The energy of the incident wave and reflected wave is distributed around the antinodes. The energy is a property of the wave as a whole.

Energy is neither created nor destroyed. The reflected waves simply cancel the vibration out through destructive interference at particular points on the wave, thus nodes exist.

Conclusion:

No. The energy of the incident wave and reflected wave is distributed around the antinodes. The energy is a property of the wave as a whole.