text: what is the physical aspect of differential equations? graphical aspect and physical meaning. charecteristics of physical systems is defined by differential equation. for example  a second order linear differential equation can define an rlc circuit. an antennae and it's polar diagram can be defined by a legendre differential equation from which the whole antennae can be described and designed. a bessel differential equation can define movement of planets in space. this can also be used to define cetain type of electrical cirucuits. butterworth, chebyshev etc; polynomials define certain other type of electrical circuits. so basically these are mathematical models of physical systems.