Linear Element are those element which follow the ohm's law.
Like as Resistance,Inductor&Capacitor(at relexed condition)
Bilateral network is that network in which any element of
the network gives the response in both directions e.g R,L,C
but diode gives the response in only one direction so it is
a unilateral element.
linear networks are those in which parameter does not
change due to change in direction....
Bilateral networks in which ratio of the response
variable to excitation variable does not change if we
interchange the position of response and excitation in the
bilateral network:A network or circuit in which the mgnitude
of the current remains the same whwn the voltage polarity is
linear network: Anetwork in which the parameters of
resistance, inductance and capacitance are constant with
respect to current or voltage and in which the voltage or
current of souurces is independent of or directly
proportional to other voltages and currents or their
derivatives in the network