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PUMPA - SMART LEARNING
எங்கள் ஆசிரியர்களுடன் 1-ஆன்-1 ஆலோசனை நேரத்தைப் பெறுங்கள். டாப்பர் ஆவதற்கு நாங்கள் பயிற்சி அளிப்போம்
Book Free DemoLet \(S\) and \(L\) represent the source and listener, respectively, moving at velocity and . Consider the case of the source and the listener approaching each other as shown in the below diagram.
![Screenshot 2021-08-24 121318.png](https://resources.cdn.yaclass.in/e2923b4b-b896-40a7-b5b4-30aee06995cf/Screenshot20210824121318w300.png)
Source and the listener
The apparent frequency will be greater than the actual source frequency as the distance between them decreases.
Let \(n\) and \(n'\) represent the frequency of the sound produced by the source and the sound heard by the listener. The apparent frequency n' is then expressed as
Here, \(v\) is the velocity of sound waves in the given medium. Let us consider different possibilities of motions of the source and the listener. In all such cases, the expression for the apparent frequency is given in the below table.
Case no | Position of source and listener | Note | Expression for apparent frequency |
1. |
| a) Distance between source and listener decreases. b) Apparent frequency is more than actual frequency. | |
2. |
| a) Distance between source and listener increases. b) Apparent frequency is less than actual frequency. c) and become opposite in \(case-1\). | |
3. |
| a) Apparent frequency depends on the velocity of the source and the listener. b) becomes opposite to that in \(case-2\). | |
4. |
| a) Apparent frequency depends on the velocity of the source and the listener. b) and become opposite to that in \(case-3\). | |
5. |
| a) Distance between source and listener decreases. b) Apparent frequency is more than actual frequency. c) \(=\) \(0\) in \(case-1\). | |
6. |
| a) Distance between source and listener increases. b) Apparent frequency is less than actual frequency. c) \(=\) \(0\) in \(case-2\). | |
7. |
| a) Distance between source and listener decreases. b) Apparent frequency is more than actual frequency. c) \(=\) \(0\) in \(case-1\). | |
8. |
| a) Distance between source and listener increases. b) Apparent frequency is less than actual frequency. c) \(=\) \(0\) in \(case-2\). |