JEE Main 2021 · PhysicsNumerical answerNumerical valueEasyCalculation

JEE Main 3 August 2021, Shift 2, Physics Q22

Question 22 of 90 in this shift, Physics question 22 of 30, Section B.

The magnetic flux linked with a coil at any instant 't' is given by

\phi = 5t^3 - 100t + 300

(SI unit). The emf induced in the coil at t = 2 s is

\underline{\hspace{2em}}

Official answer

NTA final key.

Chapter: Electromagnetic Induction
Topic: Faraday's Law
Idea tested: Faraday's Law Magnitude

Same idea in other shifts

Asked 8× in all

5 Apr 2026, Shift 2 · Q50A circular loop of radius 20 cm and resistance 2 $\Omega$ is placed in a time varying magnetic field $\vec{B}=(2t^2+2t+3)\ \mathrm{T}$ . At…EasyNumerical value
6 Apr 2026, Shift 2 · Q39A square loop of side 2 cm is placed in a time varying magnetic field with magnitude as $B=0.4\sin(300t)$ Tesla. The normal to the plane…MediumSingle correct
29 Jan 2024, Shift 1 · Q58A square loop of side 10 cm and resistance $0.7\,\Omega$ is placed vertically in east-west plane. A uniform magnetic field of $0.20\ T$ is…EasyNumerical value
31 Jan 2024, Shift 2 · Q58The magnetic flux $\phi$ (in weber) linked with a closed circuit of resistance $8\ \Omega$ varies with time (in seconds) as…EasyNumerical value
11 Apr 2023, Shift 1 · Q53The magnetic field B crossing normally a square metallic plate of area 4 m $^2$ is changing with time as shown in figure. The magnitude of…EasyNumerical valueHas a figure
25 Jul 2021, Shift 1 · Q26A circular conducting coil of radius 1 m is being heated by the change of magnetic field $\vec{B}$ passing perpendicular to the plane in…MediumNumerical value
8 Jan 2020, Shift 1 · Q14At time t = 0 magnetic field of 1000 Gauss is passing perpendicularly through the area defined by the closed loop shown in the figure. If…MediumSingle correctHas a figure

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.