Write down the properties of electromagnetic waves.

Explanation

Properties of electromagnetic waves:
(1) Electromagnetic waves are produced by any accelerated charge.
(ii) Electromagnetic waves do not require any medium for propagation. So electromagnetic wave is a non-mechanical wave.
(iii) Electromagnetic waves are transverse in nature. This means that the oscillating electric field vector, oscillating magnctic field vector and propagation vector (gives direction of propagation) are mutually perpendicular to each other.
(iv) Electromagnetic waves travel with speed which is equal to the speed of light in vacuum or free space, `c=(1)/sqrt(epsi_(0) u_(0)) =3 xx 10^(8) ms^(-1)`
(v) The speed of electromagnetic wave is less than speed in free space or vacuum, that is, `v lt c.` In a medium of refractive index, `mu_(0)= c/v= ((1)/sqrt(epsi_(0)u_(0)))/((1)/sqrt(epsi mu)) rArr = sqrt(epsi_(r) mu_(r))`.