JEE Mains · Physics · STD 11 - 14. waves and sound
A musician using an open flute of length \(50\,cm\) produces second harmonic sound waves. A person runs towards the musician from another end of a hall at a speed of \(10 \,km/h.\) If the wave speed is \(330\,m/s,\) the frequency heard by the running person shall be close to...... \(Hz\)
- A \(666\)
- B \(753\)
- C \(500\)
- D \(333\)
Answer & Solution
Correct Answer
(A) \(666\)
Step-by-step Solution
Detailed explanation
\(f=\frac{2}{2 \ell} V_{s}=\frac{330}{0.5}=660 \mathrm{Hz}\) \( \therefore \quad f^{\prime}=f\left(\frac{v_{s}+v}{v_{s}}\right)=(660)\left(\frac{330+\frac{50}{18}}{330}\right)=660\left(1+\frac{50}{18 \times 330}\right)\) \(=666 \mathrm{Hz}\)
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