The propagation constant of a wave is also calle its

Options

A. wavelength
B. frequency
C. wave number
D. angular wave number

Explanation

To solve the question regarding the propagation constant of a wave, we need to understand the definitions and relationships between the terms mentioned.

### Step-by-Step Solution:

1. **Identify the Terms**: We have several terms related to waves: wavelength, frequency, wave number, and angular wave number. We need to determine which of these is synonymous with the propagation constant.

2. **Understand Propagation Constant**: The propagation constant is a measure of how a wave propagates through a medium. In wave mechanics, it is commonly denoted by the symbol \( k \).

3. **Define Wave Number**: The wave number \( k \) is defined as the number of wavelengths per unit distance. It is mathematically expressed as:
\[ k = \frac{2\pi}{\lambda} \]
where \( \lambda \) is the wavelength.

4. **Compare with Other Terms**:
- **Wavelength (\( \lambda \))**: This is the distance between successive crests of a wave.
- **Frequency (\( \nu \))**: This is the number of waves that pass a point in one second.
- **Angular Wave Number**: This is related to the wave number and is defined as \( \kappa = \frac{2\pi}{\lambda} \), which is essentially the same as the wave number.

5. **Conclusion**: Since the propagation constant \( k \) is defined as the wave number, we conclude that the propagation constant of a wave is also called its wave number.

### Final Answer:
The propagation constant of a wave is also called its **wave number**.

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