JEE Main 2021 · PhysicsNumerical answerNumerical valueEasyCalculation

JEE Main 24 February 2021, Shift 2, Physics Q27

Question 27 of 90 in this shift, Physics question 27 of 30, Section B.

A cylindrical wire of radius 0.5 mm and conductivity

5 \times 10^7\ \mathrm{S/m}

is subjected to an electric field of

10\ \mathrm{mV/m}

. The expected value of current in the wire will be

x^3\pi

mA. The value of

x

is __________.

Official answer

NTA final key.

Chapter: Current Electricity
Topic: Ohm's Law and Resistance
Idea tested: Current Density Vector and Flux

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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.