Question

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?

Answer 1

271.2 - 243

Answer 2

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

Answer 3

This doesn't give me the correct answer