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  9. Q86

RRB NTPC 2025 · Question 86 of 409

If i is the angle of incidence and r is the angle of refraction, which relation is correct according to Snell’s law?

  1. Asin i ÷ sin r = constant
  2. Bsin i × sin r = constant
  3. Csin i + sin r = constant
  4. Dsin i – sin r = constantCorrect

Answer: D. sin i – sin r = constant

Official answer key verified. Detailed explanation coming soon.

Source: RRB NTPC Graduate CBT-2 response sheet 13-Oct-2025 Shift-1 (candidate-shared copy of official answer-key viewing) · official-answer-key

← Q85View full paper (409 questions)Q87 →

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