Sound at 50 kHz can be used by police to measure a car's speed in a speed trap. If a car is travel at a speed relative to the source of the sound, a beat frequency will be produced when the sound returns to the source. The fast the car is moving, the larger the beat frequency produced. If the speed limit in a neighborhood is 40 mph, what is the largest beat frequency produced by a car still traveling at the speed limit? Assume that the speed trap is set up to bounce sound waves off the back of a car as it is driving directly away from the source of sound.
Frequently Asked Questions
What scientific concept do you need to know in order to solve this problem?
Our tutors have indicated that to solve this problem you will need to apply the Beats concept. You can view video lessons to learn Beats. Or if you need more Beats practice, you can also practice Beats practice problems.
How long does this problem take to solve?
Our expert Physics tutor, Jeffery took 5 minutes and 41 seconds to solve this problem. You can follow their steps in the video explanation above.