JEE Main 2021 · PhysicsNumerical answerNumerical valueMediumCalculation

JEE Main 18 March 2021, Shift 1, Physics Q28

Question 28 of 90 in this shift, Physics question 28 of 30, Section B.

Two separate wires A and B are stretched by 2 mm and 4 mm respectively, when they are subjected to a force of 2 N. Assume that both the wires are made up of same material and the radius of wire B is 4 times that of wire A. The length of the wires A and B are in the ratio of a : b. Then

\frac{a}{b}

can be expressed as

\frac{1}{x}

where

x

is __________.

Official answer

NTA final key.

Chapter: Mechanical Properties of Solids
Topic: Elasticity
Idea tested: Elastic Moduli

Same idea in other shifts

Asked 13× 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 42 of the 174 JEE Main shifts held from 2017 to 2026.