Question

The disc of a siren revolves $600$ times in one minute and it is in unison with a tuning fork of frequency $480Hz$. The number of holes in the disc is :

• A. $24$
• B. $38$
• C. $48$
• D. $56$

Answer 1

The correct option is C $48$

Here,

Frequency of disc of siren is 600 per minute,

i.e.$\frac{600}{10}seconds=10sec$.

$Numberofholes=\frac{FrequencyofTuningFork}{Frequencyofsoundsource}$

$Numberofholes=\frac{480}{10}$

Number of holes = 48

Thus option C is correct.