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 at the center of a solenoid is directly proportional to: 310
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 ∝ nI, n=turns per unit length.
318
Final Answer: Option C — Both current and turns per unit length
315