A train on a straight track sounds a 400 Hz horn when passing a parked car on the road. The train is moving at 20 m/s and the temperature is 10°C. Find the apparent frequency of the horn for a person sitting inside the car when the train is approaching and when the train is moving away.

At rest, a car’s horn sounds at a frequency of 550Hz. When the horn is sounded, while the car is moving down a street, a bicyclist moving at 8.50m/s in the direction opposite to the car hears a frequency of 575Hz. (a) What is the speed of the car? (b) If the cyclist slows down to 2.50m/s before passing the car, what is the new frequency detected by the cyclist? Assume that the car moves with the same speed, and that the speed of sound in air is 343m/s.

(a) What frequency is received by a person watching an oncoming ambulance moving at 105 km/h and emitting a steady 713 Hz sound from its siren? The speed of sound on this day is 345 m/s. (b) What frequency does she receive after the ambulance has passed?

t’s a 10.5 °C spring day, and a high-speed chase is being recorded for the 36th sequel of The Quick and the Angry. A police car is chasing after a muscle car on a major highway. The police car is moving at 56.0 m/s toward the muscle car and the muscle car is moving at 60.0 m/s away from the police car. Given that the observed frequency of the siren is 398.5 Hz, what is the true frequency of the siren?

A train approaches a platform at a speed of 30 km/h while it blows its whistle. Someone on the platform hears the whistle at 275 Hz. Calculate the actual frequency of the whistle. (speed of sound = 343 m/s)

A fire truck moving at 60 m/s sounds its siren whose frequency is 1320 Hz. A car is moving in the same direction as the ambulance at 30 m/s. What frequency does a person in the car hear (a) as the ambulance approaches the car? (b) After the ambulance passes the car?

An alert physics student stands beside the tracks as a train rolls slowly past. He notes that the frequency of the train whistle is 489 Hz when the train is approaching him and 468 Hz when the train is receding from him. Using these frequencies, he calculates the speed of the train. What value does he find? (Assume the speed of sound in air is 343 m/s.) m/s Need Help? Read It

Two trains on separate tracks move toward each other. Train 1 has a speed of 149 km/h; train 2, a speed of 95.0 km/h. Train 2 blows its horn, emitting a frequency of 500 Hz. What is the frequency heard by the engineer on train 1?

(a) What frequency is received by a person watching an oncoming ambulance moving at 105 km/h and emitting a steady 753 Hz sound from its siren? The speed of sound on this day is 345 m/s. Hz(b) What frequency does she receive after the ambulance has passed? Hz

A red train is stationary and a green train is moving forward away from the red train at a speed of 28 m/s. Between the trains, is a bicyclist moving towards the stationary red train at a speed of 15.3 m/s. each train has a whistle with a frequency of 349 Hz. the air temperature is 2 degrees celsius.  What are the frequencies of the whistles heard by the bicyclist, coming from the green and red trains? PLEASE INCLUDE UNITS AND ROUND TO 4TH DECIMALS PLACE.