Physics

Color Code for Carbon Resistor

The first two bands from the end indicate the first two significant figures of the resistance in ohms. The third band indicates the decimal multiplier. The...

Ohm’s Law

The electric current I flowing through a substance is proportional to the voltage V across its ends, i.e., V ∝ I V = RI, where R...

Mobility

As we have seen, conductivity arises from mobile charge carriers. In metals, these mobile charge carriers are electrons; in an ionized gas, they are...

Drift Velocity

The average velocity gained by the free electrons of a conductor in the opposite direction of the externally applied electric field is called Drift...

Electric Current

The flow of electric charges through a conductor constitutes an electric current. Quantitatively, the electric current in a conductor across an area held perpendicular...

Energy stored in a Capacitor

Energy stored in a capacitor The energy U stored in a capacitor of capacitance C, with charge Q and voltage V is The electric energy density...

Capacitance of a Parallel Plate Capacitor

Capacitance of a parallel plate capacitor A parallel plate capacitor consists of two large plane parallel conducting plates separated by a...

Combination of Capacitors in Series and in Parallel

Capacitors in series: Fig.a shows capacitors C1 and C2 combined in series. Fig.a. Combination of two capacitors in series ...

Capacitors and Capacitance

Capacitors A capacitor (formerly known as condenser) is a device that can store electronic charge and energy. All...

Dielectrics and Polarisation

Dielectrics Dielectrics are non-conducting substances. In contrast to conductors, they have no or the negligible number of charge carriers. In a dielectric, free movement of...