As you stand near a railroad track, a train passes by at a speed of 34.5 m/s while sounding its horn at a frequency of 215 hz. what frequency do you hear as the train approaches you and what frequency while it recedes? take the speed of sound in air to be 341 m/s.

when train is approaching then the frequency is 239.2 Hz

when train is moving away  then the frequency is 195.25 Hz    

Explanation:

given,

speed of train = 34.5 m/s

Frequency of sound = 215 Hz

speed of sound = 341 m/s

a) when train is approaching

          f₁ = 239.2 Hz                                

when train is approaching then the frequency is 239.2 Hz

b) when the train is moving away

         f₂ = 195.25 Hz      

when train is moving away  then the frequency is 195.25 Hz                

0.19 m/s and 0.45 m/s

d₁ = displacement of tern from arctic to antarctic = 11000 miles

d₂ = displacement of tern from antarctic to arctic =   - 11000 miles

d = total displacement for the journey

total displacement for the journey is given as

d = d₁ + d₂

d = 11000 + (-11000)

d = 0 miles

t₁ = time of travel from arctic to antarctic = 3 months = 3 x 30 days = 90 days

t₂ = time of travel from antarctic to arctic = 3 months = 3 x 30 days = 90 days

t = total time of travel

total time of travel is given as

t = t₁ + t₂

t = 90 + 90

t = 180 days

average velocity is given as

average velocity = total displacement/ total time

v = d/t

v = 0/180

v = 0 miles/day