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प्रश्न
Lights of different colours are used as signal for safety transport. From these, the wavelength of red light is _______ nm.
विकल्प
400
500
600
700
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उत्तर
Lights of different colours are used as signal for safety transport. From these, the wavelength of red light is 700 nm.
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संबंधित प्रश्न
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(c) under special conditions
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