A train, standing at the outer signal of a railway station blows a whistle of frequency 400Hz in still air. (i) What is the frequency of the whistle for a platform observer when the train (a) approaches the platform with a speed of `10ms^(-1)` , (b) receeds from the platform with a speed of `10ms^(-1)`? (ii) What is the speed of sound in each case ? The speed of sound in still air can be taken as `340ms^(-1)`

Explanation

To solve the problem, we will use the Doppler effect formula for sound. The formula for the apparent frequency \( f' \) observed by a stationary observer when the source of sound is moving is given by:

\[ f' = f \times \frac{v + v_o}{v - v_s} \]

where:
- \( f' \) is the apparent frequency,
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