A big circular coil with \(1000\) turns and an average radius of \(10~\text{m}\) is rotating about its horizontal diameter at a rate of \(2~\text{rad s}^{-1}.\) The vertical component of the Earth's magnetic field at that location is \(2\times 10^{-5}~\text{T},\) and the electrical resistance of the coil is \(12.56~\Omega,\) the maximum induced current in the coil will be:

1.	\(2~\text{A}\)	2.	\(0.25~\text{A}\)
3.	\(1.5~\text{A}\)	4.	\(1~\text{A}\)

The current in an inductor of self-inductance \(4~\text{H}\) changes from \(4~ \text{A}\) to \(2~\text{A}\) in \(1~ \text s\). The emf induced in the coil is:
1. \(-2~\text{V}\)
2. \(2~\text{V}\)
3. \(-4~\text{V}\)
4. \(8~\text{V}\)

The magnetic flux linked to a circular coil of radius \(R\) is given by:
\(\phi=2t^3+4t^2+2t+5\) Wb.
What is the magnitude of the induced EMF in the coil at \(t=5\) s?
1. \(108\) V
2. \(197\) V
3. \(150\) V
4. \(192\) V

For a coil having \(L=2~\text{mH},\) the current flow through it is \(I=t^2e^{-t}.\) The time at which emf becomes zero is:
1. \(2\) s
2. \(1\) s
3. \(4\) s
4. \(3\) s