The dimension of the ratio of magnetic flux and the resistance is equal to that of:

The figure shows a part of a complete circuit. The potential difference $V_B - V_A$ when the current $I$ is $5 \ A$ and is decreasing at a rate of $10^3 \ A \ s^{-1}$ is given by ........ $V$.

Column $I$ gives certain situations in which a straight metallic wire of resistance $R$ is used and Column $II$ gives some resulting effects. Match the statements in Column $I$ with the statements in Column $II$.

Column $I$	Column $II$
$(A)$ $A$ charged capacitor is connected to the ends of the wire	$(p)$ $A$ constant current flows through the wire
$(B)$ The wire is moved perpendicular to its length with a constant velocity in a uniform magnetic field perpendicular to the plane of motion	$(q)$ Thermal energy is generated in the wire
$(C)$ The wire is placed in a constant electric field that has a direction along the length of the wire	$(r)$ $A$ constant potential difference develops between the ends of the wire
$(D)$ $A$ battery of constant emf is connected to the ends of the wire	$(s)$ Charges of constant magnitude appear at the ends of the wire

Write down the names of two devices which work on the principle of electromagnetic induction.

The switch $S$ shown in the circuit is closed at $t=0$. The ratio of the current drawn from the battery by the circuit at $t=0$ and $t=\infty$ is:

An $AC$ generator converts