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A police car is chasing a large vehicle at a speed of 33.0 m/s. The siren on the police car is emitting sound at a frequency of 1400 Hz. The vehicle is running away at a speed of 22.0 m/s. Determine the frequency of the sound reflected by the large vehicle as heard by police in the police car.
A truck driving at 16.5 m/s emits a sound of frequency 420 Hz from its horn in motionless air. Calculate the frequency heard by a driver in a vehicle traveling in the opposite direction and receding from the truck at 25.0 m/s.
A 2.0 W, 2.5 KHz sound emitter is released 180 m above a detector. The atmospheric temperature is 22°C. Find the i) frequency and ii) the sound intensity level detected by the detector 5.5 s from the instant the emitter was released.
A motorcycle rider blows a whistle as he rides towards a stationary observer at 65.0 km/h. The whistle emits a 2.50 kHz frequency wave, and the speed of sound in the air at that instant is 342 m/s. Determine the frequency heard by the observer.
A self-driving drone navigates in space by emitting bursts of sound waves and detecting reflections from objects. If a navigation sound has a frequency of 22 kHz, determine the speed and direction of the drone relative to an object if it detects a frequency of 18 kHz.
A siren on a blazing house emits sound at a frequency f. A firefighter approaches the siren on the blazing house at a speed vf. Derive an expression of the frequency, fr, of waves reflecting from the fire truck towards the siren. Express the result using f, vf, and speed of sound in air, v.
A teacher develops a simple method to investigate the fundamentals of the Doppler effect using acoustic waves. The teacher uses a tuning fork to produce a sound of frequency fs. During the experiment, a student riding a bike equipped with a microphone and a sound system approaches the tuning fork at a constant speed. The sound system emits a sound signal toward the class students sitting behind the tuning fork. Assume that students hear a sound with a frequency of 1.03 fs from the sound system. Calculate the bike's speed.