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When a sound wave is reflected, it’s energy decreases thus its amplitude decrease. But why is frequency unchanged?
Frequency is proportional to a wave’s energy, isn’t it?
3 Answers
- Jeffrey KLv 72 years agoFavorite Answer
Energy is only proportional to frequency for light waves. E = hf
It is not the case for sound waves.
- supastremphLv 62 years ago
To be more detailed with Jeff's answer, energy is only proportional to frequency for *photons*, that is, individual constituents of light. A beam of light still has an intensity in the classical sense. A "phonon" would be the sound wave equivalent.
- DixonLv 72 years ago
How could it change? The pressure at the surface changes in time as the wave arrives and leaves, so the frequency is unchanged.
