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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
State the energy conversion taking place in a cathode ray tube
Write one use of cathode ray tube.
Give a scientific explanation.
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What do you mean by Atomic number
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(Take ln 2 = 0.693)
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