COMEDK · Physics · 16. Waves and Sound
The disc of a siren containing 60 holes rotates at a constant speed of \(360 \mathrm{rpm}\). The emitted sound is in unison with a tuning-fork of frequency
- A \(10 \mathrm{~Hz}\)
- B \(360 \mathrm{~Hz}\)
- C \(216 \mathrm{kHz}\)
- D \(6 \mathrm{~Hz}\)
Answer & Solution
Correct Answer
(B) \(360 \mathrm{~Hz}\)
Step-by-step Solution
Detailed explanation
The number of waves produced by the disc is equal to number of notes i.e., \(\quad n=60\) Speed of rotation, \(v=360 \mathrm{rpm}\) \(=\frac{360}{60}=6 \mathrm{rps}\) \(\therefore\) Frequency \(=n \times v=60 \times 6=360 \mathrm{~Hz}\)
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