Solved UPSC CDS/OTA Question
A solved UPSC CDS/OTA PYQ — decoded step-by-step.
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Q · MagnetismDifficult · 45s
A toroid has 500 turns and carries 2 A current. Mean radius is 10 cm. Magnetic field inside is: 233
TopicMagnetism
Question Typemultiple choice
DifficultyDifficult
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
Every step explained — no skipped algebra.
B = μ₀NI/(2πr) = (4π×10⁻⁷×500×2)/(2π×0.1) = 2×10⁻³ T.
241
Final Answer: Option A — 2×10⁻³ T
236