\(\frac{\sqrt8}{\Pi}\)
\(\sqrt{\frac{8}{3}}\)
The correct answer is (B): \(\sqrt{\frac{8}{3}}\)

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 the value of \( n \) is _____. 