Electrostatics

After the demonstration of electromagnetic waves by Hertz, electromagnetic waves in different regions of wavelength were produced by different ways of excitation. Fig: Electromagnetic spectrum…

A choke coil is an inductance coil of very small resistance used for controlling current in an a.c. circuit. It is a part used in…

In an a.c circuit the current and emf vary continuously with time. Therefore power at a given instant of time is calculated and then its…

A choke coil is an inductance coil of very small resistance used for controlling current in an a.c. circuit. If a resistance is used to…

Series resonance or voltage resonance in RLC circuit The value of current at any instant in a series RLC circuit is given by I =…

The series resonant circuit is often called an ‘acceptor’ circuit. By offering minimum impedance to current at the resonant frequency it is able to select…

Let an alternating source of emf be connected across a resistor of resistance R. The instantaneous value of the applied emf is e = E0…

An alternating source of emf is connected across a capacitor of capacitance C (Figure: a). It is charged first in one direction and then in…

Rotating coil in a magnetic field, induces an alternating emf and hence an alternating current. Since the emf induced in the coil varies in magnitude…

Working Process of transformer A transformer consists of primary and secondary coils insulated from each other, wound on a soft iron core. To minimise eddy…