A car sounding its horn at 480 hz moves towards a high wall at a speed of 20 m/s . If the speed of sound is 340 ms^(-1) , the frequency of the reflected sound heard by the man sitting in the car will be nearest to :

A car sounding its horn at 480 hz moves towards a high wall at a speed

1.	A car sounding its horn at 480 hz moves towards a high wall at a speed of 20 m/s . If the speed of sound is 340 ms^(-1) , the frequency of the reflected sound heard by the man sitting in the car will be nearest to :
Answer» 480 Hz 540 Hz 510 Hz 570 Hz Solution :The apparent frequency striking the wall is `v. = ((V)/(V - U_(s))) . V = (340xx480)/(340 - 20) = 510 ` Hz After reflection the wall ACTS as source and man sitting in the car as observer who is moving towards the wall. `thereforev.. = ((V + U_(0))/(V) ) . v. = ((340 + 20)/(340) ) 510= 540 `Hz. thus CORRECT CHOICE is (B).

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A car sounding its horn at 480 hz moves towards a high wall at a speed of 20 m/s . If the speed of sound is 340 ms^(-1) , the frequency of the reflected sound heard by the man sitting in the car will be nearest to :

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