JEE Main 2020 · PhysicsMultiple choiceSingle correctMediumApplication

JEE Main 9 January 2020, Shift 2, Physics Q8

Question 8 of 75 in this shift, Physics question 8 of 25, Section A.

Two steel wires having same length are suspended from a ceiling under the same load. If the ratio of their energy stored per unit volume is

1:4

, the ratio of their diameters is :

(1) $1:\sqrt{2}$
(2) $1:2$
(3) $\sqrt{2}:1$ Official answer
(4) $2:1$

Official answer

Option 3

NTA final key (Jan 2020).

Chapter: Mechanical Properties of Solids
Topic: Elasticity
Idea tested: Elastic Energy Density

Same idea in other shifts

Asked 4× in all

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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.