Magnetic Flux Definition and Unit

Magnetic Flux is defined as; “a total number of lines of magnetic force passing through any surface placed perpendicular to the magnetic field. It is denoted by φ (Greek Letters Phi). Magnetic Flux Formula The magnetic flux is also defined as the dot product of magnetic field B and vector Area …

Potentiometer Variable Resistor Working Principle

A potentiometer or a rheostat is an instrument used to measure and compare potentials without drawing any current from the circuit. Potentiometer Principle The potential difference across any length of wire of uniform cross-section area is directly proportional to its length where a constant current flows through it. A potentiometer consists …

Magnetomotive Force (MMF) Definition

Magnetomotive force is defined as, “The force produced by current through a coil of wire is called magnetomotive force (mmf), as shown in the following figure. It is the force by which a magnetic field is produced. Just as an increase in electromotive force produces more current in a circuit, …

Wheatstone Bridge Circuit Theory and Working Principle

Wheatstone bridge is used to measure unknown resistance and is defined by the circuit of the following figure. In above Figure, R1, R2, and R3 are known resistances and Rx is the resistance whose value is to be determined. At least one of the known resistances is variable. The variable resistance is …

RC Series Circuit Analysis | RC Time Constant

In the case of a resistive-capacitive (RC) series circuit, when the supply is first switched on the charging current is initially at its maximum level, then it gradually falls to zero. The capacitor voltage is zero at first and grows gradually to its maximum level. As with the RL Circuit, …

Magnetic Force on a Current Carrying Conductor

A current carrying conductor produces its own magnetic field. Such a conductor is placed in a magnetic field. The magnetic field of the conductor will interact with the external magnetic field. As a result of which the conductor may experience a force. It can be observed by the following experiment. …

Resistors in Series and Parallel

Resistance Resistance is defined as the measure of opposition to the motion of electrons due to their continuous collisions, with the atoms of the conductor. The unit of resistance is ohm. Let’s consider the conductor of cross-sectional area A and of length L as given below: The resistance of this …

AC Energy Meter Working Principle

Energy is the product of power and time and is measured in watt-seconds or Joule. Since the voltage and current in a DC circuit are constant values, the energy is easily computed from a measurement of power and time, $W=Pt~~~~~~~~~~Joule$ Where W is in watt-seconds or Joules, P in watts …

Capacitors in Series and Capacitors in Parallel

A capacitor is a passive device which stores energy in an electric field and opposes the change in voltage. An electric field can be created by placing two conducting plates in parallel and having one plate more positive than other as shown in fig. The material between two plates is …

Difference Between Diamagnetism, Paramagnetism, and Ferromagnetism

In order to classify materials as magnetic or non-magnetic, it must be determined whether or not forces act on the material when a material is placed in a magnetic field. If a bar of any given material is suspended in a magnetic field, it will either turn at a right …

Power Measurement In a Three-Phase System using Wattmeter

Wattmeter is an instrument, used to measure power in a circuit using current and voltage of the circuit. The wattmeter is essentially an electrodynamic mechanism, in which the stationary and movable coils separately measure the current and voltage of the circuit, as shown in Fig. The stationary coil is designed …

RL Series Circuit Analysis

When a resistive-inductive (RL) series circuit has its supply voltage switched on, the inductance produces an initial maximum level of counter-emf that gradually falls to zero. The circuit current is zero initially and grows gradually to its maximum level. The behavior of an RL series circuit is most easily understood …

Magnetic lines of Force | Magnetic Field

When current flows in a wire, it creates a magnetic effect around the wire which is called magnetic field. The magnetic field is specified by a direction as well as a magnitude. The following figure shows a magnetic field, of a bar magnet, by field lines that originate from the …