how does a doppler radar work a science with bobert video short

This is an animation of how a Doppler radar system works for determining what is going on with our local weather. The information gathered from a Doppler radar system includes how far away precipitation is and how intense. But where the Doppler Effect comes in is when the radar system determines which way the rain drops are moving! Pulses of radio waves are sent from the Doppler radar which bounce off precipitation in the clouds. The radar system determines how far away and intense the precipitation is and uses the Doppler Effect to determine just how fast toward or away the precipitation is moving from the radar system.

Astronomers use the Doppler effect too. Did you know that our universe is expanding? Astronomers know this because of the Doppler Effect. Light from every surrounding galaxy is shifted to lower frequencies indicating that these galaxies are moving away from each other. Astronomers do not know if this expansion is going to continue or stop and reverse itself.

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The doppler effect occurs for both sound and light.

The Doppler Effect is the change in frequency of sound/light as it moves toward or away from an observer. The frequency of sound/light increases when the source moves toward the obsever and decreases when the source moves away from the observer

Either the observer, the source, or both have to be moving for a Doppler Effect to occur!

Doppler radar determines the direction and speed raindrops are moving!

Astronomers know our universe is expanding because of the Doppler Effect