JEE Main 2021 · PhysicsMultiple choiceSingle correctMediumCalculation

JEE Main 16 March 2021, Shift 2, Physics Q19

Question 19 of 90 in this shift, Physics question 19 of 30, Section A.

Find out the surface charge density at the intersection of point

x=3

m plane and

x

-axis, in the region of uniform line charge of 8 nC/m lying along the

z

-axis in free space.

(1)47.88 C/m
(2) $0.07\ \mathrm{nC\,m^{-2}}$
(3) $0.424\ \mathrm{nC\,m^{-2}}$ Official answer
(4) $4.0\ \mathrm{nC\,m^{-2}}$

Official answer

Option 3

NTA final key.

Chapter: Electric Charges and Fields
Topic: Electric Field
Idea tested: Finite/Infinite Line Field

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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 42 of the 174 JEE Main shifts held from 2017 to 2026.