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Two train whistles A and B each have a f...

Two train whistles A and B each have a frequency of 220 Hz. A is stationary and B is moving toward the right (away from A) at a speed of `35 m//s` . A listener between the two trains is moving towards the right with a speed of `15 m//s` . No wind is blowing.
What is frequency from A as heard by the listener

Text Solution

Verified by Experts

`n_A=n_B`=220 Hz
Apparent frequency as heard from `A=220((330-15)/330)`=210 Hz
(b) Apparent frequency as heard from `B=220((330+15)/(330+35))`=208 Hz
(c ) Beat frequency detected by the listener = 210-208 =2 Hz
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