The difference between the apparent frequency of a source of sound as perceived by an observer during its  approach and recession  is 2% of the natural frequency of the source. If the velocity of sound in air is 300 m/sec, the velocity of the source is (It is given that velocity of source << velocity of sound)The difference between the apparent frequency of a source of sound as perceived by an observer during its  approach and recession  is 2% of the natural frequency of the source. If the velocity of sound in air is 300 m/sec, the velocity of the source is (It is given that velocity of source << velocity of sound)