Question

42. Define and explain in detail.
(0) Velocity of propagation.
(ii) Wave impedance.
(iii) Depth of penetration.
(iv) Group velocity​

Answer 1

Answer:

(0) Velocity of propagation. answer ho jaye ji

Answer 2

a) The velocity factor, also called wave propagation speed or velocity of propagation, of a transmission medium is the ratio of the speed at which a wavefront passes through the medium, to the speed of light in vacuum. For optical signals, the velocity factor is the reciprocal of the refractive index.

b) The wave impedance of an electromagnetic wave is the ratio of the transverse components of the electric and magnetic fields. For a transverse-electric-magnetic plane wave traveling through a homogeneous medium, the wave impedance is everywhere equal to the intrinsic impedance of the medium.

c) Penetration depth is a measure of how deep light or any electromagnetic radiation can penetrate into a material. It is defined as the depth at which the intensity of the radiation inside the material falls to 1/e of its original value at the surface.

d) The group velocity of a wave is the velocity with which the overall envelope shape of the wave's amplitudes—known as the modulation or envelope of the wave—propagates through space.