An observer moves towards a stationary source of sound with speed (1)/(5) th of the speed of sound. The wavelength and frequency of sound emitted are lambda and f respectively. The apparent frequency and wavelength recorded by the observer are respectively :

An observer moves towards a stationary source of sound with speed (1)/

1.	An observer moves towards a stationary source of sound with speed (1)/(5) th of the speed of sound. The wavelength and frequency of sound emitted are lambda and f respectively. The apparent frequency and wavelength recorded by the observer are respectively :
Answer» 1.2 F, 1.2 `lambda` f,1.2 ` lambda` `1.2 f, lambda` `0.8 f, 0.8 lambda`. Solution :When observer moves towards stationary SOURCE then f. `= ((V + U_(0))/(V)) `f `f ((V + (V)/(5))/(V)) ` f f. = 1.2 f . WAVELENGTH is not affected by the MOTION of observer. CORRECT choice is c.

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An observer moves towards a stationary source of sound with speed (1)/(5) th of the speed of sound. The wavelength and frequency of sound emitted are lambda and f respectively. The apparent frequency and wavelength recorded by the observer are respectively :

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