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प्रश्न
Which of the following sources provides the best monochromatic light?
पर्याय
A candle
A bulb
A mercury tube
A laser
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उत्तर
A laser
Among the given sources, laser is the best coherent source providing monochromatic light with constant phase difference.
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संबंधित प्रश्न
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(ii) Does the decrease in speed imply a reduction in the energy carried by light wave?
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