Linear elements
A linear element is one whose plot
between, voltage across it and the current through it, comes out to be a
straight line.
In other words, elements for which impedance remains
constant for all values of voltage across them.
Examples :- resistors, inductors, capacitors etc.
Linear Circuits
The circuits that contain only linear elements are
called linear circuits. An example of linear circuit is shown below.
If a graph is
drawn between the voltage applied (V) to the circuit and the current flowing (I) through the circuit, it comes out to be a straight
line, as shown in above figure, proving it a linear circuit.
Non Linear elements
A non-linear element (opposite of
linear element) is one whose impedance changes when the voltage applied across
it is changed.
i.e Elements which do not follow Ohm's law are called non-linear elements.
Examples :- Pn junction diode, BJT, JFT, MOSFET or
semiconductor devices in general.
For such devices, the plot between, voltage across
them and the current through them, do not come out to be a straight line.
Non Linear Circuits
The circuits that contain at least one non-linear
element are called non-linear circuits. An example of non-linear circuit is shown
below.
If a graph is drawn between the voltage applied to the
circuit (V) and the current flowing through the circuit (I) , it does not come
out to be a straight line, showing the circuit is a non-linear circuit.
Related concepts :-
(1) Ohm's law
