Solved UPSC CDS/OTA Question
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Q · Current ElectricityMedium · 45s
The value of Coulomb’s constant (k) in SI units is approximately: Option: 15
TopicCurrent Electricity
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
Every step explained — no skipped algebra.
Coulomb’s constant k = 1/(4πε₀) ≈ 8.99 × 10⁹ Nm²/C².
15
Final Answer: Option A — 8.99 × 10⁹ Nm²/C²
15