question_answer

Will there be any Doppler effect, if both the sound and the listener are moving with the same velocity and in the same direction?

Answer:

                The apparent frequency is given by \[v'=\frac{\upsilon -{{\upsilon }_{0}}}{\upsilon -{{\upsilon }_{s}}}\times v\] As\[{{\upsilon }_{0}}={{\upsilon }_{s}},\] therefore, \[v'=v\] i.e. there is no Doppler effect.