An engine standing at the platform blows a whistle of frequency 305 vib/sec. if the velocity of sound be 1220 km/h, the frequency of the whistle as heard by a man towards the engine with a speed of 20 km/h is :

An engine standing at the platform blows a whistle of frequency 305 vi

1.	An engine standing at the platform blows a whistle of frequency 305 vib/sec. if the velocity of sound be 1220 km/h, the frequency of the whistle as heard by a man towards the engine with a speed of 20 km/h is :
Answer» 300 vib/s 305 vib/s 310 vib/s 320 vib/s Solution :`V. = ((V + U_(0))/(V) )v = (1220 + 20)/(1220) . 305= `310 HZ. Hence the correct choicer is (c).

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An engine standing at the platform blows a whistle of frequency 305 vib/sec. if the velocity of sound be 1220 km/h, the frequency of the whistle as heard by a man towards the engine with a speed of 20 km/h is :

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