The disc of a siren containing 60 holes rotates at a constant speed of – McqOptions

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1.	The disc of a siren containing 60 holes rotates at a constant speed of 360 rpm. The emitted sound is in unison with a tuning fork of frequency [KCET 2005]
A.	10 Hz
B.	360 Hz
C.	216 Hz
D.	6 Hz
Answer» C. 216 Hz

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