Two cars A and B are moving away from each
other in opposite directions. Both the cars are
moving with a speed of 20 ms
–1
with respect
to the ground. If an observer in car A detects
a frequency 2000 Hz of the sound coming from
car B, what is the natural frequency of the sound
source in car B ?
(speed of sound in air = 340 ms
–1
) :-