Physics · Electromagnetic Induction

JEE Main 2025 — 28 January, Evening Shift — Question 64

A conducting bar moves on two conducting rails as shown in the figure. A constant magnetic field $B$ exists into the page. The bar starts to move from the vertex at time $t=0$ with a constant velocity. If the induced EMF is $E \propto t^{n}$ , then value of $n$ is $\qquad$ ..

Question figure

Answer: 1

Numerical answer — enter this value.

Step-by-step solution

$\mathrm{E}=\ell \mathrm{vB}$

$E=\frac{2 x}{\sqrt{3}} \times v B$ and $x=v t$

$E=\frac{2}{\sqrt{3}} v^{2} B t \quad E \propto t^{1}$

Solution figure

Answer key and solution verified before publishing.

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Exam: JEE Main 2025
Paper: 28 January, Evening Shift
Subject: Physics
Chapter: Electromagnetic Induction
Topic: Motional EMF

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