JEE Main 2021 · PhysicsMultiple choiceSingle correctMediumApplication

JEE Main 3 August 2021, Shift 1, Physics Q11

Question 11 of 90 in this shift, Physics question 11 of 30, Section A.

Two conducting spheres of radii 15

cm

and 12

cm

are charged and joined by a wire. The ratio of electric fields on the surfaces of the first and the second sphere is -

(1) $\frac{4}{5}$ Official answer
(2) $\frac{5}{4}$
(3) $\frac{16}{25}$
(4) $\frac{64}{125}$

Official answer

Option 1

NTA final key.

Chapter: Electrostatic Potential and Capacitance
Topic: Conductors in Fields
Idea tested: Field at Conductor Surface

Same topic in other shifts

All Conductors in Fields questions

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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.