JEE Main 2022 · MathsMultiple choiceSingle correctMediumMulti-step

JEE Main 24 June 2022, Shift 1, Maths Q3

Question 3 of 90 in this shift, Maths question 3 of 30, Section A.

The surface area of a balloon of spherical shape being inflated, increases at a constant rate. If initially, the radius of balloon is 3 units and after 5 seconds, it becomes 7 units, then its radius after 9 seconds is :

(1)9Official answer
(2)10
(3)11
(4)12

Official answer

Option 1

NTA final key (2022 Session 1).

Chapter: Application of Derivatives
Topic: Chain Rule
Idea tested: Chain Rule in Related Rates

Same topic in other shifts

All Chain Rule questions

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16 Mar 2021, Shift 2 · Q79Let $f:S\to S$ where $S=(0,\infty)$ be a twice differentiable function such that $f(x+1)=xf(x)$ . If $g:S\to\mathbf R$ be defined as…HardSingle correct

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.