The change in frequency due to Doppler effect does not depend on

A. the speed of the source


B. the speed of the observer


C. the frequency of the source


D. separation between the source and the observer


The apparent frequency due to the Doppler effect ν' = {V/(V-U)}*ν₀ or depending upon the source moves towards the observer or the observer moves towards the source. Thus the change in frequency due to Doppler effect depends on V, U and ν₀ only. It does not depend on the separation between the source and the observer.

So the option D is correct.

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