Given.
Frequency, v = 2 kHz = 2000Hz
Wavelength, `lambda` = 35 cm = 0.35 m
We know that speed, v of the wave
= wavelength `xx` frequency
v = `lambda` v
= o.35 m`xx` 2000 Hz = 700 m/s
The time taken by the wave to travel a distance, d of 1.5 km is
`t=(d)/(v)=(1.5xx1000 m)/(700ms^(-1))=(15)/(7)s=2.1 s.`
Thus sound will take 2.1 s to travel a distance of 1.5 km.
