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a doopler speet meter

December 14, 2020

A Doppler speed meter operating at exactly 1.02Af—105 Hz emits sound waves and detects the same waves after they are reflected from a baseball thrown by the pitcher. The receiver “mixes” the reflected wave with a small amount of the emitted wave and measures a beat frequency of 0.30Af—105 Hz.

How fast is the ball moving?