At what speed should a source of sound moves so that observer find that apparent frequency equal to half of the original frequecy ?

At what speed should a source of sound moves so that observer find tha

1.	At what speed should a source of sound moves so that observer find that apparent frequency equal to half of the original frequecy ?
Answer» `(v)/(2)` 2V `(v)/(4)` v Solution :`v. = ((V)/(V + U_(s)) ) vrArr2V = (V + U_(s))` `U_(s) ` = V Hence the CORRECT CHOICE is (d) .

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At what speed should a source of sound moves so that observer find that apparent frequency equal to half of the original frequecy ?

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