Give four applications of photoelectric cell.

Give four applications of photoelectric cell. 
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Answer :

i) It is used in Lux-meter ii)It is used for automatic control of traffic signals iii)It is used to switch on and off automatically the street lights. iv)It is used in recording and reproduction of sound during shooting of film. v)It is used in television sets, fire alarms vi)It is used in Exposure meter.
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