Question
The whistle of an approaching engine appears to be shriller than that of a preceding engine. Why?
Solution
When the source moves towards the observer the apparent frequency is,
When source moves away from the observer, then apparent frequency is,
The ratio of this frequency is given by,
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#6 {main}</pre>](/application/zrc/images/qvar/PHEN11040256-3.png)
When source moves away from the observer, then apparent frequency is,
The ratio of this frequency is given by,
