Police radar guns measure the speed of moving vehicles by transmitting electromagnetic waves at a vehicle and detecting a Doppler shift in the reflected wave. Suppose a police radar transmits at a frequency of 23.8 GHz and receives wave reflected from a car moving toward the radar at 75.0 mph. (a) Find the frequency shift Af=fo - fg (in Hz) between the observed (received) and source (transmitted) frequencies. Hz (b) If the beat frequency measurement in part (a) is accurate to +5.5 Hz, how accurate is the speed measurement? m/s

Police radar guns measure the speed of moving vehicles by transmitting electromagnetic waves at a vehicle and detecting a Doppler shift in the reflected wave. Suppose a police radar transmits at a frequency of 23.8 GHz and receives wave reflected from a car moving toward the radar at 75.0 mph. (a) Find the frequency shift Af=fo - fg (in Hz) between the observed (received) and source (transmitted) frequencies. Hz (b) If the beat frequency measurement in part (a) is accurate to +5.5 Hz, how accurate is the speed measurement? m/s

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter21: Alternating-Current Circuits And Electromagnetic Waves

Section: Chapter Questions

Problem 65P: Police radar guns measure the speed of moving vehicles by transmitting electromagnetic waves at a...

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