JEE Main 20205 Sep, Evening shiftPhysicsMediumOscillations and Waves185× since 2002
A driver in a car, approaching a vertical wall
notices that the frequency of his car horn, has
changed from 440 Hz to 480 Hz, when it gets
reflected from the wall. If the speed of sound in
air is 345 m/s, then the speed of the car is :