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TEA [102]
3 years ago
14

Which description best explains how a Doppler radar system works?

Physics
1 answer:
Irina-Kira [14]3 years ago
8 0

Answer: A.  It reflects waves off of objects, measuring the difference of the waves it sends and receives.

Explanation:

A Doppler radar uses the Doppler effect when measuring return echoes after having sent a signal (in this specific case microwaves).

In this context the Doppler effect consists of the change in a wave perceived frequency when the emitter of the waves, and the receiver (or observer in the case of light) move relative to each other.  

In the case of radars, a microwave signal is sent to a target and then reflected, so that the radar system measures this difference between the sent signal and the reflected signal.

It should be noted that this effect bears its name in honor of the Austrian physicist <u>Christian Andreas Doppler</u>, who in 1842 proposed the existence of this effect for the case of light in the stars. Another important aspect is that the effect occurs in all waves (including light and sound). However, it is more noticeable to humans with sound waves.

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