AP EAMCET · PHYSICS · Waves and Sound
A police car moving at \(22 \mathrm{~ms}^{-1}\) chases a motor cyclist. The police man sounds horn at \(176 \mathrm{~Hz}\), while both of them move towards a stationary siren of frequency \(165 \mathrm{~Hz}\). If the number of beats heard by the motor cyclist per second is zero, then the speed of motorcycle is ( Speed of sound in air \(=330 \mathrm{~ms}^{-1}\))
- A \(33 \mathrm{~ms}^{-1}\)
- B \(22 \mathrm{~ms}^{-1}\)
- C \(44 \mathrm{~ms}^{-1}\)
- D \(11 \mathrm{~ms}^{-1}\)
Answer & Solution
Correct Answer
(B) \(22 \mathrm{~ms}^{-1}\)
Step-by-step Solution
Detailed explanation
According to the question, we draw the following situation, Given, velocity of car, \(v_{s_1}=22 \mathrm{~ms}^{-1}\) speed of the sound in air, \(v=330 \mathrm{~ms}^{-1}\) apparent frequency by cyclist from the police car,…
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