Question

a sound wave has frequency 2hz and wavelength 40 cm how will long will it take to travel 1.6 km

Answer 1

frequency = n=2kHz= 2x1000 Hz
Wavelength= 40cm= 40/100=0.4m
Speed of sound: V= frequency * wavelength
                              =2×1000×0.4
                             =800m/s

Speed=Distance/ time
Distance= 1.6km= 1.6x1000m
Time= distance/ speed
= 1.6x1000/ 800
=16×100/800
=2sec.

Answer 2

frequency × wavelength =velocity
frequency =2hz
wavelength =40cm=40/100m
velocity =2×40/100=0.8m/s
distance/velocity =time taken
distance =1.6km=1600m
time=1600/0.8= 2000sec