Wavelength of a siren in air is 1.2m. And if same siren is blown under water it has wavelength 6 m in water. Find the velocity of sound in water, if the speed of sound in air is 330 m/s.

Asked by Topperlearning User | 30th Dec, 2013, 12:40: AM

Expert Answer:

Let v1, v2 be the velocities of sound in air and water respectively.
Wavelength of sound waves in air λ1 = 1.2 m
Wavelength of sound waves in water λ2 = 6 m
Since, source of sound is same, frequency will be same
vl νλ1
330 m/s = ν x 1.2
ν = 330/1.2                                         …(1)
 
Velocity of sound in water
v2 = ν  λ2
ν = v2/6                                               …(2)
From equation 1 and 2 we get
330/ 1.2 = v2 /6
v2 = 330 x 6/1.2 = 1650 m/s is the velocity of sound wave in water.

Answered by  | 30th Dec, 2013, 02:40: AM