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Saturday, 31 October

JEE Main 2024 · PhysicsNumerical answerNumerical valueHardMulti-step

JEE Main 27 January 2024, Shift 1, Physics Q55

Question 55 of 90 in this shift, Physics question 25 of 30, Section B.

A thin metallic wire having cross sectional area of 10−410^{-4} m2^2 is used to make a ring of radius 30 cm. A positive charge of 2π2\pi C is uniformly distributed over the ring, while another positive charge of 30 pC is kept at the centre of the ring. The tension in the ring is ________ N; provided that the ring does not get deformed (neglect the influence of gravity). (given, 14πϵ0=9×109\frac{1}{4\pi\epsilon_0} = 9\times10^{9} SI units)

Official answer

3

NTA final key.

Chapter
Electric Charges and Fields
Topic
Coulomb's Law
Idea tested
Self-Repulsion Tension in a Charged Ring

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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.