A coil 10 turns and a resistance of $$40 \Omega$$ is connected in series with B.G. of resistance $$30 \Omega$$. The coil is placed with its plane perpendicular to the direction of a uniform magnetic field of induction $$10^{-2} \mathrm{~T}$$. If it is now turned through an angle of $$60^{\circ}$$ about on axis in its plane. Find the charge indicted in the coil. (Area of a coil $$=10^{-2} \mathrm{~m}^2$$ )

A disc of $$10.0 \mathrm{~cm}$$ diameter is rotated at speed of $$3600 \mathrm{~rpm}$$ inside a long solenoid of 1200 turns per metre on the axis of the solenoid and perpendicular to the plane of the disc. When a current of $$1.5 \mathrm{~A}$$ is passed through the solenoid, the difference in the potential between axes and circumference of the disc is nearly

The induced emf in a coil of $$10 \mathrm{H}$$ inductance in which current varies from $$9 \mathrm{~A}$$ to $$4 \mathrm{~A}$$ in $$0.2 \mathrm{~s}$$ is

A conductor of length $$5 \mathrm{~cm}$$ is moved parallel to itself with a speed of $$2 \mathrm{~m} / \mathrm{s}$$, perpendicular to a uniform magnetic field of $$10^{-3} \mathrm{~Wb} / \mathrm{m}^3$$. The induced e.m.f. generated is