JEE Mains · Physics · STD 11 - 14. waves and sound
Two cars are approaching each other at an equal speed of \(7.2\, km / hr\). When they see each other, both blow horns having frequency of \(676\, Hz\). The beat frequency heard by each driver will be \(.....\, Hz\). [Velocity of sound in air is \(340\,m / s .]\)
- A \(8\)
- B \(16\)
- C \(32\)
- D \(24\)
Answer & Solution
Correct Answer
(A) \(8\)
Step-by-step Solution
Detailed explanation
Frequency of sound heard by car\(-1,\) which comes by reflection from car\(-2\) \(f _{1}= f _{0}\left(\frac{340+2}{340-2}\right)\left(\frac{340+2}{340-2}\right)\) \(= f _{0}\left(\frac{342}{338}\right)^{2}\) Frequency of sound coming directly from car\(-2\)…
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