JEE Main 2022 · PhysicsMultiple choiceSingle correctEasyApplication

JEE Main 26 July 2022, Shift 1, Physics Q39

Question 39 of 90 in this shift, Physics question 9 of 30, Section A.

B_X

and

B_Y

are the magnetic fields at the centre of two coils X and Y respectively each carrying equal current. If coil X has 200 turns and 20 cm radius and coil Y has 400 turns and 20 cm radius, the ratio of

B_X

and

B_Y

is :

(1) $1:1$
(2) $1:2$ Official answer
(3) $2:1$
(4) $4:1$

Official answer

Option 2

NTA final key.

Chapter: Moving Charges and Magnetism
Topic: Biot-Savart Law
Idea tested: Field at center of circular arc

Same idea in other shifts

Asked 8× in all

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3 Aug 2021, Shift 1 · Q13A current I enters a circular coil of radius R, branches into two parts at A and then recombines at B (as shown in figure). The resultant…MediumDiagram basedHas a figure
4 Sep 2020, Shift 1 · Q13A wire A, bent in the shape of an arc of a circle, carrying a current of 2 A and having radius 2 cm and another wire B, also bent in the…MediumDiagram basedHas a figure

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.