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प्रश्न
What are cathode rays? Why are they called ‘cathode rays’? Name a material which exhibits fluorescence when cathode rays fall on it.
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उत्तर
Cathode rays are the stream of negatively charged particles called electrons. They are called cathode rays because they are given out from cathode in a discharge tube operating at about 10,000 V when the pressure inside the tube is about 0.01 mm of Hg. Zinc Sulphide exhibits fluorescence when cathode rays fall on it.
संबंधित प्रश्न
What happens if the negative potential is changed on a grid?
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1) Name the radiation B which is unaffected by the electrostatic field.
2) Why does the radiation C deflect more than A?
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[ln (0.15) = -1.9]
