If a wave of wavelength `lambda` is travelling in a medium with velocity V, then its frequency is

Options

A. `V/lambda`
B. `Vlambda`
C. `lambda/V`
D. `1/(Vlambda)`

Answer

To find the frequency of a wave given its wavelength (\( \lambda \)) and velocity (\( V \)), we can use the relationship between wave speed, frequency, and wavelength.

### Step-by-Step Solution:

1. **Understand the Relationship**: The speed of a wave (\( V \)) is related to its frequency (\( n \)) and wavelength (\( \lambda \)) by the formula:
\[ V = n \cdot \lambda \]
Here, \( V \) is the speed of the wave, \( n \) is the frequency, and \( \lambda \) is the wavelength.

2. **Rearranging the Formula**: To find the frequency (\( n \)), we can rearrange the formula:
\[ n = \frac{V}{\lambda} \]
This means that the frequency of the wave is equal to the velocity of the wave divided by its wavelength.

3. **Substituting the Values**: If we have the values of \( V \) (velocity) and \( \lambda \) (wavelength), we can substitute them into the rearranged formula to calculate the frequency.

4. **Conclusion**: Thus, the frequency of the wave is given by:
\[ n = \frac{V}{\lambda} \]

### Final Answer:
The frequency of the wave is \( n = \frac{V}{\lambda} \).

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