A motor car blowing a horn of frequency 124vib/sec moves with a velocity 72 km/hr towards a tall wall. The frequency of the reflected sound heard by the driver will be (velocity of sound in air is 330 m/s)
(1) 109 vib/sec
(2) 132 vib/sec
(3) 140 vib/sec
(4) 248 vib/sec
(3) Similar to previous question
The frequency of reflected sound heard by the driver
= 140 vibration/sec.