Which of the following wave phenomenon is not shown by sound wave ?

Options

A. Interference
B. Diffraction
C. Polarisation
D. Doppler's effect

Answer

To determine which wave phenomenon is not exhibited by sound waves, we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Understanding Wave Phenomena**:
- Waves can exhibit various phenomena such as interference, diffraction, polarization, and the Doppler effect.

2. **Analyzing Each Option**:
- **Option 1: Interference**:
- Sound waves can interfere with each other. When two sound waves of the same frequency meet, they can create regions of constructive and destructive interference. This phenomenon is commonly observed in acoustics.
- **Conclusion**: Sound waves do show interference.

- **Option 2: Diffraction**:
- Sound waves can also diffract. This occurs when sound waves pass through an opening or around obstacles. The extent of diffraction depends on the wavelength of the sound relative to the size of the opening or obstacle.
- **Conclusion**: Sound waves do show diffraction.

- **Option 3: Polarization**:
- Polarization is a phenomenon that occurs only in transverse waves. In transverse waves, the oscillations are perpendicular to the direction of wave propagation. Sound waves, however, are longitudinal waves, where the oscillations occur in the same direction as the wave travels. Therefore, sound waves cannot be polarized.
- **Conclusion**: Sound waves do not show polarization.

- **Option 4: Doppler Effect**:
- The Doppler effect is a change in frequency or wavelength of a wave in relation to an observer moving relative to the wave source. This effect is well-known in sound waves, such as when a moving vehicle approaches and then recedes from an observer.
- **Conclusion**: Sound waves do show the Doppler effect.

3. **Final Answer**:
- Among the options analyzed, the phenomenon that is not shown by sound waves is **Polarization** (Option 3).

### Summary:
The wave phenomenon that is not exhibited by sound waves is **Polarization**.

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