JEE Main 2022 · MathsMultiple choiceSingle correctMediumMulti-step

JEE Main 25 June 2022, Shift 2, Maths Q11

Question 11 of 90 in this shift, Maths question 11 of 30, Section A.

Water is being filled at the rate of

1\ \mathrm{cm}^3 / \mathrm{sec}

in a right circular conical vessel (vertex downwards) of height 35 cm and diameter 14 cm. When the height of the water level is 10 cm, the rate (in

\mathrm{cm}^2 / \mathrm{sec}

) at which the wet conical surface area of the vessel increases is

(1)5
(2) $\frac{\sqrt{21}}{5}$
(3) $\frac{\sqrt{26}}{5}$ Official answer
(4) $\frac{\sqrt{26}}{10}$

Official answer

Option 3

NTA final key.

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

Same idea in other shifts

Asked 5× 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.