NTA Abhyas JEE Main2020PhysicsWaves and SoundPractice
In a car race, sound signals emitted by the two cars are detected by a detector on the straight track at the end of the race. The frequency observed for the two cars is 330 Hz and 360 Hz respectively, while the original frequency is 300 Hz for both the cars. The race ends with a separation of 100 m between the cars. Assume both cars move with constant velocity and velocity of sound is 330 m s - 1 . Find the time take
Correct answer
4.00
Step-by-step solution
330 = 330 330 − v 1 × 300 ⇒ v 1 = 30 m s - 1 360 = 330 330 − v 2 × 300 330 − v 2 = 330 12 × 10 = 275 v 2 = 55 m s - 1 ; ΔV = 25 m s - 1 100 = ΔV × T ⇒ T = 4 s