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प्रश्न
Give the applications photocell.
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उत्तर
Applications of photocells:
- Photocells have many applications, especially as switches and sensors.
- Automatic lights that turn on when it gets dark use photocells, as well as street lights that switch on and off according to whether it is night or day.
- Photocells are used for the reproduction of sound in motion pictures and are used as timers to measure the speeds of athletes during a race.
- Photocells are used to measure the intensity of the given light and to calculate the exact time of exposure.
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