B) A train passing through a station with velocity 80 m/s by blowing horn at frequency 512 Hz. Calculate the frequency of sound heard a person standing on a platform.
(i) When the train is approaching.
(ii) When the train is receding.

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Solution

Dear Student,

(i) Frequency of the horn, v= 400Hz
Speed of the train, vT=10m/s
Speed of sound, v= 340m/s
The apparent frequency (v′) of the horn as the train approaches the platform is given by the
relation: v′=(v−vrv)v
=(340−10340)×400=412.12Hz

(ii) The apparent frequency (v′) of the horn as the train recedes from the platform is given by the relation:
v′′=(v+vrv)v
=(340+10340)×400=388.57Hz

Regards.

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B) A train passing through a station with velocity 80 m/s by blowing horn at frequency 512 Hz. Calculate the frequency of sound heard a person standing on a platform. (i) When the train is approaching. (ii) When the train is receding.

B) A train passing through a station with velocity 80 m/s by blowing horn at frequency 512 Hz. Calculate the frequency of sound heard a person standing on a platform.
(i) When the train is approaching.
(ii) When the train is receding.