Electromagnetic...

Mutual induction of the system of two coils do not depends upon

The figure shows a circular area of radius $$R$$ where a uniform magnetic field $$\vec B$$ is going into the plane of the paper and increasing in magnitude at a constant rate. In that case, which of the following graphs, drawn schematically, correctly shows the variation of the induced electric field $$E(r)$$?

Two coils are made of copper wires of the same length In the first coil the number of turns is 3$$\mathrm { n }$$ and radius is $$r .$$ In the second coil number of turns is $$\mathrm { n }$$ and radius is 3$$\mathrm { r }$$ the ratio of self-inductances of the coils will be:-

Two coils A and B have mutual inductance $$2\times { 10 }^{ -2 }$$ henry. If the current in the primary is $$i=5\sin { \left( 10\pi t \right)  } $$ then the maximum value of e.m.f. induced in coil B is

A conducting disc of radius R rotates about its axis with an angular velocity $$\omega$$. Then the potential difference between the centre of the disc and its edge is ( no magnetic field is present) 

An average induced emf of 0.4 V appears in a coil when the current in it is changed from 10 A in one direction to 10 A in opposite direction in 0.5 sec. self-inductance of the coil is.

A conducting circular loop made of a thin wire, has area $$3.5\times 10^{ -3 }m^{ 2 }$$ and resistance 10 $$\Omega $$. It is placed perpendicular to a time dependent magnetic field B(t)=(0.4T)sin(50$$\pi $$t). The field is uniform in space. Then the net charge flowing through the loop during t=0 s and t=10 ms is close to :

In an A.C. sub-circuit as shown in figure, the resistance $$R = 0.2 \Omega$$. At a certain instant $$V_A -V_B = 0.5 V$$, $$l =0.5 A$$, and current is increasing at the rate of $$\frac{\triangle l}{\triangle t} = 8 A/s$$. The inductance of the coil is

Two coaxial coils are very close to each other and their mutual inductance is 5 mH.If a current l=10 sin 500 t  is passed in one coil, then the peak value of induced emf in secondary coil is (where l is in A and t is in s)

A coil is wound on a hollow insulating cylinder, which contains in it a laminated iron core. The dependence of inductance L with the displacement X  of the iron core is shown in the figure. In the initial state X= 0 (the core is fully inserted into the coil), the current in the coil is 1.0 A. Find current in the coil immediately after the core is quickly taken out of the coil