A toothed wheel is rotated at 120 r.p.m and a post-card is placed aginest the teeth. How many teeth (frequency) must the wheel have to produce a note whse pitch is same as that of a tunning fork of frequency 256/ second ?

A toothed wheel is rotated at 120 r.p.m and a post-card is placed agin

1.	A toothed wheel is rotated at 120 r.p.m and a post-card is placed aginest the teeth. How many teeth (frequency) must the wheel have to produce a note whse pitch is same as that of a tunning fork of frequency 256/ second ?
Answer» `256` 120 64 32 Solution :Here n = no. of TEETH `xx ` no. of re/sec. `256 = (120)/(60) xx m` m ` = (60 xx 256)/(120) = 12.8 ` HENCE the CORRECT choice is (d).

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A toothed wheel is rotated at 120 r.p.m and a post-card is placed aginest the teeth. How many teeth (frequency) must the wheel have to produce a note whse pitch is same as that of a tunning fork of frequency 256/ second ?

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