An engine whistling at a constant frequency n_(0) and moving with a constant velocity goes past a stationery observer. As the engine crosses him, the frequency of the sound heard by him changes by a factor f. The actual difference in the frequencies of the sound heard by him before and after the engine crosses him is

An engine whistling at a constant frequency n_(0) and moving with a co

1.	An engine whistling at a constant frequency n_(0) and moving with a constant velocity goes past a stationery observer. As the engine crosses him, the frequency of the sound heard by him changes by a factor f. The actual difference in the frequencies of the sound heard by him before and after the engine crosses him is
Answer» `(1)/(2)n_(0)(1-F^(2))` `(1)/(2)n_(0)((1-f^(2))/(f))` `n_(0)((1-f)/(1+f))` `(1)/(2)n_(0)((1-f)/(1+f))` Answer :B

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