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प्रश्न
Explain, why radium paint, consisting of zinc sulphide and a trace of radium salt, glows in the dark?
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उत्तर
Radium is a radioactive substance. It gives out radioactive radiations which show fluorescence in zinc sulphide. Zinc sulphide is a fluorescent material, so it glows in dark.
संबंधित प्रश्न
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