*81. CD A car is parked 20.0 m directly south of a railroad crossing. A train is approaching the crossing from the west, headed directly east at a speed of 55.0 m/s. The train sounds a short blast of its 289-Hz horn when it reaches a point 20.0 m west of the crossing. What frequency does the car's driver hear when the horn blast reaches the car? The speed of sound in air is 343 m/s. (Hint: Assume that only the component of the train's velocity that is directed toward the car affects the frequency heard by the driver.)

The speed of sound in air is 330 m s-¹ 1. A motorcyclist travelling at a speed of 29 m s-¹ sounds the horn on their motorbike while passing a pedestrian beside the road. The rider hears the horn as a sound of frequency 250 Hz. a. What frequency does the pedestrian hear: i. when the motorcycle approaches? ii. when the motorcycle moves away? b. Explain why, when the motorcycle is right in front, the pedestrian hears the same frequency as the rider. D

how would you do this as isn't the ambulance the source of the sound? this is a non graded practice worksheet

1. A car is blowing its horn (f = 285Hz) while driving away from you at 18.0m/s. The air temperature is -12.0°C. a) What frequency do you hear? b) How fast would the car have to drive, and in what direction, for you to hear a frequency of 356Hz?