Question

a sound wave has a frequency of 4 kilohertz and wavelength of 40 cm the time taken by the sound wave to travel a distance of 3.2 km is ?

Answer 1

distance = 3.2 km
frequency = 4 hz
ladma = 0.4 m
velocity = 0.4×4 = 1.6 m/sec
time = d/v
3.2/1.6 = 2sec

Answer 2

Answer:

Time taken by the sound wave, t = 2 seconds

Explanation:

It is given that,

Frequency of sound wave, f = 4 kHz = 4000 Hz

Wavelength of sound wave, λ = 40 cm = 0.4 m

We have to find the time taken by the sound wave to travel a distance of 3.2 km,  $d=3.2\times 10^3\ m$

Velocity of sound is given by :

$v=f\times \lambda$

$v=4000\ Hz\times 0.4\ m$

v = 1600 m/s

Velocity of wave is also given by distance travelled per unit time.

$t=\dfrac{d}{v}$

$t=\dfrac{3.2\times 10^3\ m}{1600\ m/s}$

t = 2 seconds

Hence, this is the required solution.