Solved UPSC CDS/OTA Question
A solved UPSC CDS/OTA PYQ — decoded step-by-step.
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Q · MagnetismModerate · 45s
The magnetic field due to a long straight current-carrying conductor decreases with distance as: 145
TopicMagnetism
Question Typemultiple choice
DifficultyModerate
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
Every step explained — no skipped algebra.
B = μ₀I/(2πr) ⇒ ∝ 1/r.
153
Final Answer: Option A — 1/r
148