$A$ coil is placed perpendicular to a magnetic field of $5000 \,T$. When the field is changed to $3000 \,T$ in $2 \,s$, an induced emf of $22 \,V$ is produced in the coil. If the diameter of the coil is $0.02 \,m$, then the number of turns in the coil 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

$A$ uniform magnetic field $\vec{B}$ is perpendicular to the plane of a circular loop of diameter $10 \text{ cm}$ formed from a wire of diameter $2 \text{ mm}$ and resistivity $2 \times 10^{-8} \Omega \text{ m}$. If a current of $11 \text{ A}$ is to be induced in the loop, then the rate at which $\vec{B}$ is to be changed is: (in $\text{ T s}^{-1}$)

Magnetic flux linked with the coil in weber is given by the equation $\phi = 5t^2 + 6t + 11$. The e.m.f. induced in the coil in the $5^{\text{th}}$ second will be (in $\text{ V}$)

The figure shows planar loops of different shapes moving out of or into a region of a magnetic field which is directed normal to the plane of the loop away from the reader. Determine the direction of induced current in each loop using Lenz's law.

Lenz's law applies to