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प्रश्न
Photo diodes are used to detect ______.
विकल्प
radio waves
gamma rays
IR rays
optical signals
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उत्तर
Photo diodes are used to detect optical signals.
Explanation:
A photodiode is a semiconductor device that converts light energy into electrical current. It is mainly used to detect light or optical signals in communication systems and electronic devices. Hence, the correct answer is optical signals.
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