Electromagnetic...

In L – R circuit, for the case of increasing current, the magnitude of current can be calculated by using the formula

The current through choke coil increases from zero to 6 A in 0.3 seconds and an induced e.m.f. of 30 V is produced. The inductance of the coil of choke is

A coil of N = 100 turns carries a current I = 5 A and creates a magnetic flux ɸ =10^–5 Tm^–2 per turn. The value of its inductance L will be

Two identical induction coils each of inductance L joined in series are placed very close to each other such that the winding direction of one is exactly opposite to that of the other. What is the net inductance

The adjoining figure shows two bulbs B₁ and B₂, resistor R and an inductor L. When the switch S is turned off

If a current of 5 A in a coil of self-inductance 2 mH is cut off in time 0.1 s, the induced e.m.f. in the coil is

Which types of losses do not occur in the transformer?

An AC generator of 220 V having internal resistance r = 10 Ω and external resistance R= 100 Ω. What is the power developed in the external circuit

In step-up transformer, relation between number of turns in primary (N_p) and number of turns in secondary (N_s) coils is

The pointer of a dead-beat galvanometer gives a steady deflection becauses