JEE Mains · Physics · STD 11 - 14. waves and sound
Two engines pass each other moving in opposite directions with uniform speed of \(30\,m/s\) . One of them is blowing a whistle of frequency \(540\,Hz.\) Calculate the frequency heard by driver of second engine before they pass each other ... \(Hz\). Speed of sound is \(330\,m/sec\)
- A \(450\)
- B \(540\)
- C \(270\)
- D \(648\)
Answer & Solution
Correct Answer
(D) \(648\)
Step-by-step Solution
Detailed explanation
We know that the apperent frequency \(\mathrm{f}^{\prime}=\left(\frac{\mathrm{v}-\mathrm{v}_{0}}{\mathrm{v}-\mathrm{v}_{\mathrm{s}}}\right) \mathrm{f}\) from Doppler's effect where \(v_{0}=v_{s}=30 \mathrm{m} / \mathrm{s},\) velocity of observer and source Speed of sound…
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