A Toothed Wheel Is Rotated At 120 R.p.m. A Post Card Is Placed Against The Teeth. How Many Teeth Must The Wheel Have To Produce A Note Whose Pitch Is The Same As That Of A Tuning Fork Of Frequency 256 Hz?

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A toothed wheel is rotated at 120 r.p.m. A post card is placed against the teeth. How many teeth must the wheel have to produce a note whose pitch is the same as that of a tuning fork of frequency 256 Hz?


Correct option is



Number of revolutions per second  If x is the number of teeth then




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