As the bar moves without change in orientation, the length of bar will be proportional to its distance from the vertex. i.e. I=c(vt) $\begin{aligned}
& \text { induced emf } E=B / v \
& =c B v^2 t
\end{aligned}\Rightarrow n=1$
JEE Main 2025 — Physics Electromagnetism

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∝tn, then value of n is _.
Held on 28 Jan 2025 · Verified 6 Jul 2026.
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