A siren placed at a railwary platform is emitting sound of frequency 5 k Hz. A passenger sitting in a moving train approaches the siren. During his return journey in a different train B, he records a frequency of 6.0 K Hz. While approaching the same siren. The ratio of velocity of train B to the velocity of train A is :

A siren placed at a railwary platform is emitting sound of frequency 5

1.	A siren placed at a railwary platform is emitting sound of frequency 5 k Hz. A passenger sitting in a moving train approaches the siren. During his return journey in a different train B, he records a frequency of 6.0 K Hz. While approaching the same siren. The ratio of velocity of train B to the velocity of train A is :
Answer» 242/252 43957 2 44141 Solution :v.`= ((V + U_(0))/(V) ) v rArr 5.5 = ((V + v_(1))5)/(v) ` `v_(1) = 0.1` v In second case, 6 = `((V + v_(2))/(v) ) 5 rArr v_(2) = 0.2 `v `therefore (v_(2))/(v_(1)) = 2 `. CORRECT choice is (c).

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