JEE Main 2021 · PhysicsMultiple choiceSingle correctEasyCalculation

JEE Main 4 August 2021, Shift 1, Physics Q16

Question 16 of 90 in this shift, Physics question 16 of 30, Section A.

A steel wire of 1 mm

^2

cross-sectional area having Young’s modulus

2\times10^{11}

N/m

^2

is stretched between two fixed points at a temperature of 40°C. The tension developed in the wire when its temperature falls to 30°C is given by (Coefficient of linear expansion of steel =

11 \times 10^{-6}

/°C)

(1)22 NOfficial answer
(2)11 N
(3) $2 \times 10^6$ N
(4) $10^5$ N

Official answer

Option 1

NTA final key.

Chapter: Thermal Properties of Matter
Topic: Thermal Expansion
Idea tested: Thermal Stress

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.