JEE Main 2020 · PhysicsMultiple choiceSingle correctMediumCalculation

JEE Main 3 September 2020, Shift 1, Physics Q13

Question 13 of 75 in this shift, Physics question 13 of 25.

Magnitude of magnetic field (in SI units) at the centre of a hexagonal shape coil of side 10 cm, 50 turns and carrying current I (Ampere) in units of

\frac{\mu_0 I}{\pi}

is :

(1) $5\sqrt{3}$
(2) $50\sqrt{3}$
(3) $250\sqrt{3}$
(4) $500\sqrt{3}$ Official answer

Official answer

Option 4

NTA final key (Sep 2020).

Chapter: Moving Charges and Magnetism
Topic: Biot-Savart Law
Idea tested: Field at Center of Regular Polygon

Same idea in other shifts

Asked 5× in all

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Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.