The ratio of the apparent frequencies of a car when approaching and receding a stationary observer is 11:9 What is the speed of the car, if the velocity of sound in air is 330 m/s?

Explanation

To solve the problem, we will use the Doppler effect equations for sound waves. The steps are as follows:

### Step 1: Write down the Doppler Effect formulas
For a source approaching a stationary observer, the apparent frequency \( f' \) is given by:
\[ f' = \frac{v}{v - v_s} \cdot f \]
For a source receding from a stationary observer, the apparent frequency \( f'' \) is given by:
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