You are traveling in a car toward a hill at a speed of 40.8 mph. The car's horn emits sound waves of frequency 243 Hz, which move with a speed of 340 m/s.The frequency with which the waves strike the hill is 254.7Hz and the frequency of the reflected sound waves you hear 271.2 Hz.
What is the beat frequency produced by the direct and the reflected sounds at your ears?
271.2 - 243
The rest of it with the Doppler shift information is just to confuse the student. At your ear, you send 243 and get back 271.2
This doesn't give me the correct answer
To find the beat frequency produced by the direct and reflected sounds, we need to understand the concept of beats. Beats occur when two sound waves of slightly different frequencies interfere with each other. The beat frequency is the difference between the frequencies of the two sound waves.
In this scenario, we have a car moving towards a hill, emitting sound waves from its horn, and those sound waves are being reflected back to the car. The frequencies involved are:
- Frequency of the emitted sound waves: 243 Hz
- Frequency of the waves striking the hill: 254.7 Hz
- Frequency of the reflected sound waves heard by the car: 271.2 Hz
To calculate the beat frequency, we need to find the difference between the frequencies of the waves striking the hill and the reflected sound waves heard by the car.
Beat frequency = Frequency of reflected sound waves - Frequency of waves striking the hill
Beat frequency = 271.2 Hz - 254.7 Hz
Beat frequency = 16.5 Hz
So, the beat frequency produced by the direct and reflected sounds at your ears is 16.5 Hz.