Police use radar guns and the Doppler effect to catch speeders. The figure below illustrates a moving car approaching a stationary police car. A radar gun emits an electromagnetic wave that reflects from the oncoming car. The reflected wave returns to the police car with a frequency (measured by on-board equipment) that is different from the emitted frequency. One such radar gun emits a wave whose frequency is 8.0 x 10° Hz. When the speed of the car is 21.0 m/s and the approach is essentially head-on, what is the difference between the frequency of the wave returning to the police car and that emitted by the radar gun? Number Reflected electromagnetic wave Units Outgoing electromagnetic wave H₂ :

Police use radar guns and the Doppler effect to catch speeders. The figure below illustrates a moving car approaching a stationary police car. A radar gun emits an electromagnetic wave that reflects from the oncoming car. The reflected wave returns to the police car with a frequency (measured by on-board equipment) that is different from the emitted frequency. One such radar gun emits a wave whose frequency is 8.0 x 10° Hz. When the speed of the car is 21.0 m/s and the approach is essentially head-on, what is the difference between the frequency of the wave returning to the police car and that emitted by the radar gun? Number Reflected electromagnetic wave Units Outgoing electromagnetic wave H₂ :

Modern Physics

3rd Edition

ISBN:9781111794378

Author:Raymond A. Serway, Clement J. Moses, Curt A. Moyer

Publisher:Raymond A. Serway, Clement J. Moses, Curt A. Moyer

Chapter1: Relativity I

Section: Chapter Questions

Problem 18P

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