A person observes two moving trains, A reaching the station and B leaving the station with equal speed of 30 m s^(-1). If both trains emit sounds with…

Question

A person observes two moving trains, A reaching the station and B leaving the station with equal speed of 30 m s^(-1). If both trains emit sounds with frequency 300 Hz, (Speed of sound : 330 m s^(-1)) approximate difference of frequencies heard by the person will be :

MARKS Content Team · Accepted Answer

Correct answer: (B) 55 Hz. Using Doppler effect, apparent frequency is given by f=(v±v_0)/(v∓v_s)f_0, where f_0=actual frequency, v_0=velocity of observer and v_s=velocity of source For train B leaving the station, f_1=300(330-0)/(330--30)=275 Hz ∵v_0=0 For train A reaching the station, f_2=300(330-0)/(330-30)=330 Hz The difference of frequencies heard by the person∆f=330-275=55 Hz

A person observes two moving trains, $A$ reaching the station and $B$ leaving the station with equal speed of $30 m s^{- 1}$ . If both trains emit sounds with frequency $300 Hz$ , (Speed of sound : $330 m s^{- 1}$ ) approximate difference of frequencies heard by the person will be :

Solution

Relevant Questions

A person observes two moving trains, A reaching the station and B leaving the station with equal speed of 30 m s-1. If both trains emit sounds with frequency 300 Hz, (Speed of sound : 330 m s-1) approximate difference of frequencies heard by the person will be :

Solution

Relevant Questions

A person observes two moving trains, $A$ reaching the station and $B$ leaving the station with equal speed of $30 m s^{- 1}$ . If both trains emit sounds with frequency $300 Hz$ , (Speed of sound : $330 m s^{- 1}$ ) approximate difference of frequencies heard by the person will be :