A bat flies at a steady speed of 4 ms^(-1) emitting sound of f= 90 xx 10^(3) Hz. If is flying horizontally towards a vertical wall. The frequency of the reflected sound as detected by the ball will be : (take velocity of sound in air as 330 ms^(-1) )

A bat flies at a steady speed of 4 ms^(-1) emitting sound of f= 90 xx

1.	A bat flies at a steady speed of 4 ms^(-1) emitting sound of f= 90 xx 10^(3) Hz. If is flying horizontally towards a vertical wall. The frequency of the reflected sound as detected by the ball will be : (take velocity of sound in air as 330 ms^(-1) )
Answer» `92.1 xx 10^(3)` Hz `89.1 xx 10^(3)` Hz `88.1 xx 10^(3)` Hz `87.1 xx 10^(3)` Hz Solution :the FREQUENCY of reflected sound as detected by the bat will be `v. = ((v + mu_(0))/(v - u_(s)) ) ` v ` v. = ((350 + 5)/(330 - 4) ) xx 90 xx 10^(3)` `v. = 92.1 xx 10^(3) `Hz. So correct choice is a.

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A bat flies at a steady speed of 4 ms^(-1) emitting sound of f= 90 xx 10^(3) Hz. If is flying horizontally towards a vertical wall. The frequency of the reflected sound as detected by the ball will be : (take velocity of sound in air as 330 ms^(-1) )

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