Two waves of lengths 50 cm and 51 cm produce 12 beats per

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Two waves of lengths 50 cm and 51 cm produce 12 beats per sec. The velocity of sound is

1. 306 m/s
2. 331 m/s
3. 340 m/s
4. 360 m/s

Correct Option: A

Given : Wavelength of first wave (λ₁) = 50 cm = 0.5 m
Wavelength of second wave (λ₂) = 51 cm = 0.51m
frequency of beats per sec (n) = 12.
We know that the frequency of beats,

n = 12 =	v	-	v
	λ₁		λ₂

⇒ 12 = y		1	-	1
		0.5		0.51

= v[2 - 1.9608] = v × 0.0392

or, v =	12	= 306 m/s
	0.0392

[where, v = velocity of sound]