Which of the following phenomenon is not common to sound and light waves ?

Options

A. interference
B. diffaction
C. Coherence
D. Polarisation

Answer

To solve the question "Which of the following phenomena is not common to sound and light waves?", we will analyze each of the given options to determine which phenomenon is unique to light waves and not applicable to sound waves.

### Step-by-Step Solution:

1. **Understanding the Types of Waves**:
- Sound waves are **longitudinal waves**, meaning that the oscillations of the particles in the medium are parallel to the direction of wave propagation.
- Light waves are **transverse waves**, meaning that the oscillations of the electric and magnetic fields are perpendicular to the direction of wave propagation.

2. **Analyzing the Options**:
- **Option 1: Interference**: Both sound and light waves can exhibit interference. This occurs when two waves overlap and combine to form a new wave pattern.
- **Option 2: Diffraction**: Both sound and light waves can also undergo diffraction, which is the bending of waves around obstacles and openings.
- **Option 3: Coherence**: Coherence refers to the correlation between the phases of waves at different points in space and time. Both sound and light waves can be coherent.
- **Option 4: Polarization**: Polarization is a phenomenon that occurs only in transverse waves. Since light waves are transverse, they can be polarized. However, sound waves, being longitudinal, cannot be polarized.

3. **Conclusion**:
- The phenomenon that is not common to sound and light waves is **polarization**. Therefore, the correct answer is **Option 4: Polarization**.

### Final Answer:
**Polarization** (Option 4) is the phenomenon that is not common to sound and light waves.

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