Question

. A sound waves has a frequency of 2kHz and wave length is 35cm. How long will it take to travel 1.5km?

Answer 1

f= 2000hz
w.l. = .35m

speed = f × w.l.
700m/s

now dist. = 1500 m
time= d/sp.
1500/700
15/7s
2.142sec.

hope this would help u : )

Answer 2

Frequency,
                  v = 2 kHz
                     = 2000 Hz

Wavelength, 
                       λ = 35 cm
                          = 0.35 m

Speed,
            V = wavelength x Frequency
           
           V = λ x v
              = 0.35 m x 2000 Hz
             = 700 m/s

Time taken by the wave to travel distance of 1.5 km is
                 
                  t = d/v
                   
                   = (1.5 x 1000 m) / 700 ms-^1
                  
                   = 15/7 s  = 2.1 s

Hence sound will take 2.1 s to travel a distance of 1.5 km.