The frequency of a source is 20 kHz. The frequencies of sound wave produced by it in water and air will be

Options

A. same as that of source 20 kHz
B. gt 20 kHz
C. lt 20 kHz
D. depends upon velocity

Explanation

To solve the question regarding the frequency of sound waves produced by a source in different mediums (water and air), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Given Frequency**:
The frequency of the source is given as 20 kHz.

2. **Understand the Concept of Frequency**:
Frequency is defined as the number of waves that pass a point in one second. It is measured in Hertz (Hz), where 1 kHz = 1000 Hz.

3. **Recognize the Independence of Frequency**:
One key property of sound waves is that the frequency of a sound wave remains constant when it travels from one medium to another. This means that whether the sound is traveling through air or water, the frequency will not change.

4. **Apply the Concept to the Given Mediums**:
Since the frequency is independent of the medium, the frequency of the sound wave in both water and air will remain the same as the original frequency from the source.

5. **Conclude the Answer**:
Therefore, the frequency of the sound wave produced by the source in both water and air will be 20 kHz.

### Final Answer:
The frequency of sound waves produced by the source in water and air will be **20 kHz**.

---