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163. Problem 20.67 (RHK) An acoustic burglar alarm consists of a source emitting
waves of frequency 28.3 kHz. We have to find beat frequencies of waves
reflected from an intruder walking at
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directly
away from the alarm.|
Solution: Click For PDF Version Frequency of the burglar alarm,
Speed of the burglar walking away from the alarm,
Using the Doppler shift relation frequency of the signal as detected by the burglar,
Frequency of the reflected signal at the source will be further Doppler shifted as the burglar is moving away from the siren. It will be
The beat frequency will be
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.
