A current through a wire depends on time as $i=\alpha_0 t+\beta t^{2}$ where $\alpha_0=20$ A/s and $\beta=8$ As$^{-2}$. Find the charge crossed through a section of the wire in 15 s.

JEE Main 2021 · PhysicsMultiple choiceSingle correctEasyCalculation

JEE Main 24 February 2021, Shift 1, Physics Q13

Question 13 of 90 in this shift, Physics question 13 of 30, Section A.

A current through a wire depends on time as

i=\alpha_0 t+\beta t^{2}

where

\alpha_0=20

A/s and

\beta=8

^{-2}

. Find the charge crossed through a section of the wire in 15 s.

(1)260 C
(2)2100 C
(3)11250 COfficial answer
(4)2250 C

Official answer

Option 3

NTA final key.

Chapter: Current Electricity
Topic: RC Circuits
Idea tested: Total Charge Flown Integration

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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.