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In a wiper rain sensor, water drops do what to the infrared beam?
AAbsorb all of it
BDivert part of the beam
CReflect all of it back
DPolarise all of it
Answer & Solution
Correct answer: B. Divert part of the beam
With a dry outer surface the infrared beam is totally reflected to the detector, while water drops spoil the total reflection and divert part of the light.
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