The figure shows a rod of length $l$ with points $A$ and $B$ on it. The rod is moved in a uniform magnetic field $\left(B_0\right)$ in different ways as shown. In which case, the potential difference $\left(V_A-V_B\right)$ between $A$ and $B$ is minimum?

A bent rod $PQR$ $\left(PQ=QR=l\right)$ shown here is rotating about its end $P$ with an angular speed $𝝎$ in a region of transverse magnetic field of strength $B$. Then

A cylindrical space of radius $R$ is filled with a uniform magnetic induction $B$, parallel to the axis of the cylinder. If $\frac{\mathrm{d}B}{\mathrm{d}t}=\mathrm{constant}$, the graph showing the variation of induced electric field with distance $r$ from the axis of cylinder is 

The figure shows three regions of magnetic field, each of area $A$. In each region, the magnitude of magnetic field decreases at a constant rate $\alpha$. If $\overrightarrow{E}$ is the induced electric field, then the value of the line integral, $\oint \overrightarrow{E}.\overrightarrow{dl}$, along the given loop, is equal to

A uniform magnetic field of induction $B$ is confined to a cylindrical region of radius $R$. The magnetic field is increasing at a constant rate of $\frac{dB}{dt}$. A negative charge of magnitude $e$ is placed at point $P$ on the periphery of the field. Its acceleration is

As a result of the change in the magnetic flux linked to the closed loop, shown in the figure, an emf of $V \mathrm{volt}$ is induced in the loop. The work done (in $\mathrm{joule}$) in taking a charge of $Q \mathrm{coulomb}$ once along the loop is