Electromagnetic...

In an ac circuit the emf (e) and the current (i) at any instant core given respectively by e = E_osinωt, I = I_osin(ωt – φ). The average power in the circuit over one cycle of ac is.

Same current is flowing in two alternating circuits. The first circuits contains only inductance and the other contains only a capacitor. If the frequency of the emf of ac is increased the effect on the value of the current will be.

The value of alternating emf E in the given circuit will be.

In a region of uniform magnetic induction B = 10^-2 tesla, a circular coil of radius 30 cm and resistance π² ohm is rotated about an axis which is perpendicular to the direction of B and which forms a diameter of the coil. If the coil rotates at 200 rpm the amplitude of the alternating current induced in the coil is,

The power factor of a good choke coil is

When 100 volt dc is applied across a coil, a current of 1A flows through it. When 100 volt ac at 50 cyle s^–1 is applied to the same coil, only 0.5 A current flows. The impedance of the coil is,

An LC circuit contains a 20 mH inductor and a 50 μF capacitor with an initial charge of 10 mc. The resistance of the circuit is negligible. At the instant the circuit is closed be t = 0. At what time is the energy stored completely magnetic.