Statements A, B, and C are correct. Cathode rays originate from the negatively charged cathode and travel towards the positively charged anode (A). Older television and computer monitors used Cathode Ray Tubes (CRTs) to produce images (B). The beam of electrons itself is not visible to the naked eye; the light is produced when the electrons strike a fluorescent screen (C).
Which one of the following statements is not correct?
Asked in UPSC CDS 1 2017 · UPSC CDS 1 2022 · Topic: Electric Current (Definition of Electric Current and current density)
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Answer: D. The characteristics of cathode rays depend upon the nature of the gas present in the cathode-ray tube.
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