## Question

Two identical flutes produce fundamental notes of frequency 300 Hz at 27^{o}C. If the temperature of the air in one flute is increased to 31^{o}C, the number of beats heard per second will be

### Solution

2

Let *v*_{1} be the speed of sound at 27^{o}*C* and *v*_{2} at 31^{o}*C*. Then

Now, frequency ∝ speed of sound. Hence

Hence beat frequency = 302 – 300 = 2.

#### SIMILAR QUESTIONS

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