The working of a dynamo is based on the principle of

$A$ conducting coil having $500$ turns has a cross-sectional area of $0.15 \ m^2$. $A$ magnetic field of strength $0.2 \ T$ linked perpendicular to this area changes to $1.0 \ T$ in $0.4 \ s$. The induced emf produced in the coil will be . . . . . . $V$.

The magnetic flux $\phi$ through a coil varies with time $t$ as shown in the diagram. Which graph best represents the variation of the induced electromotive force (e.m.f.) $E$ in the coil with time $t$?

The north pole of a magnet is brought near a metallic ring. The direction of the induced current in the ring will be

Two conducting wire loops are concentric and lie in the same plane. The current in the outer loop is clockwise and increasing with time. The induced current in the inner loop is

State and explain Faraday's law of electromagnetic induction.