Analogy Between Electric And Magnetic Circuits

Analogy Between Electric And Magnetic Circuits Assignment Help | Analogy Between Electric And Magnetic Circuits Homework Help

Analogy Between Electric And Magnetic Circuits

As the path of an electric current is known as an electric circuit, similarly the path of magnetic flux is known as magnetic circuit.

As an electric e.m.f. is necessary to cause the flow of current in an electric circuit, similarly magneto-motive force is required to create the ma netic flux in the magnetic circuit.

As the current flowing in an electric circuit depends upon the e.m.f. and resistance of the circuit, similarly the magnetic flux or number of lines of force produced in any magnetic circuit depends upon the magneto-motive force acting in the circuit and reactance of the circuit.

Let us consider a solenoid of length l metres, turns N, cross-sectional area, a metres2 and carrying a current of I amperes.

Field strength inside the solenoid,  H = NI metre

If the solenoid is wound on magnetic substance of relative permeability μr  then

Flux density, B =μoμr H = μoμrNI 
Total flux created, θ = B X a = μoμr NI X a =   NI     =     AT     Wb
                                                               l / μoμra     l / μoμra

where AT is the product of current flowing through the solenoid and number of turns. AT is known as ampere-turns.

Hence in magnetic circuit flux created  θ = M.M.F.    just as in an electric circuit current, I = E.M.F.
                                                              reluctance                                                      resistance

The numerator AT is known as m.m.f. of the magnetic circuit and corresponds to e.m.f. in an electric circuit. The denominator l / μoμr is known as the reluctance of the magnetic circuit, which offers the resistance in creation of flux θ and corresponds to resistance in an electric circuit. It is represented by symbol S and is measured in ampere-turns per Weber.

In an electric circuit resistance, R = p   = l where K = and is known as con ductivity. Similarly in
                                                       a   Ka               p
magnetic circuit reluctance S =        =  where μ is known as absolute permeability corresponding to
                                             μoμra      μa    conductivity in an electric circuit.

But where in the electric circuit resistance causes heat to be generated resulting in waste of energy, there is no waste of energy due to reluctance in the magnetic circuit.

For more help in Analogy Between Electric And Magnetic Circuits click the button below to submit your homework assignment