Magnetic flux passing through a coil is initially $4 \times 10^{-4} \ Wb$. It reduces to $10 \%$ of its original value in $t$ seconds. If the induced emf is $0.72 \ mV$,then $t$ in seconds is:

An aluminium ring $B$ faces an electromagnet $A$. The current $I$ through $A$ can be altered.

$A$ metallic ring is placed in a room. When the north pole of a magnet is brought near to it,the induced current in the ring will be

$A$ coil of $n$ turns and resistance $R \ \Omega$ is connected in series with a resistance $R/2$. The combination is moved for time $t$ seconds through a magnetic flux change from $\Phi_1$ to $\Phi_2$. The induced current in the circuit is:

The total emf induced in a closely wound coil of $N$ turns in which the magnetic flux linked with the coil is changing at the rate $\frac{d \phi_{B}}{dt}$ is

The magnitude of induced emf is directly proportional to the rate of change of magnetic flux linked with the coil. This statement is known as