Electromagnetic...

Two coils of self-inductances $$ L_1 and L_2 $$ are placed so closed to each other that the effective flux in one coil is completely linked with the other, then the mutual inductance M between them is given by-

In a certain region static electric and magnetic fields exist. The magnetic field is given by $$\vec{B} = B_0 (\hat{i} + 2\hat{j} -4\hat{k})$$. If a test charge moving with a velocity $$\vec{v} = v_0 (3\hat{i} - \hat{j} + 2\hat{k})$$ experiences no force in that region, then the electric field in the region, in SI units, is:

A uniform but time varying magnetic field exists in cylindrical region and directed into the appear. If field decreases with time and a positive charge placed at any point inside the region, then if moves

A coil having n turns and resistance $$R\Omega$$, is connected in series with resistance $$R$$. This combination is moved in time t seconds from a magnetic field $$W_{1}$$ weber to $$W_{2}$$ weber. The induced current in the circuit is 

A thin semicircular conducting ring of radius R is falling with its plane vertical in a horizantal magnetic induction B as shown in the fig. At the position MNQ$$ the speed of the ring is v. then, the potential difference developed across the ring is

A charge of $${10^{ - 6}}C$$ is describing a circular path of radius $$1$$ cm making $$5$$ revolution per second . The magnetic induction field at the centre of the circle is 

A circular loop of radius A is placed in the same plane as a long straight wire carrying a current I. The centre of the loop is at a distance  r from the wire where r>>a . The loop is moved away from the wire with a constant velocity v. The induced emf in the loop is

A long metal rod moves at a constant velocity in the direction perpendiular to the length and at constant magnetic field. choose the correct statement

A conducting circular ring and a conducting elliptical ring both are moving pure transnationally in a uniform magnetic field of strength $$B$$ as shown in figure on a horizontal conducting pane potential difference between top most point of circle and ellipse is:

A coil having $$100$$ turns and area of $$0.001 \, m^2 $$ is free to rotate about its diametric axis; the coil is placed with its plane perpendicular to magnetic field of $$1.0 \, \dfrac{Wb}{m^2}$$. If the coil is rotated rapidly through an angle of $$180^0$$, how much charge will flow through the coil ? The resistance of the coil is $$10 \,\Omega $$