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  9. Q69

OPSC OCS 2021 · Question 69 of 72

What was the active medium used in the first working laser ever constructed ?

General Studies

  1. ADiamond block
  2. BHelium-neon gas
  3. CRuby rodCorrect
  4. DCarbon dioxide gas

Answer: C. Ruby rod

Explanation

Theodore Maiman built the first working laser using a ruby rod while working at Hughes Research Laboratories in Malibu, California. It lased for the first time on May 16, 1960.

Source: OPSC OCS Prelims 2021 GS Paper-I; answers per Apti Plus unofficial key

← Q68View full paper (72 questions)Q70 →

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