Characteristics of wavefront:
i. Wavefronts travel with the speed of light in all directions in an isotropic medium.
ii. The phase difference between any two points in the same phase on the two consecutive wavefronts is 2π. So, if the phase at a crest is 2π, then phase at next consecutive crest = 4π and so on. Hence at any crest, the phase is 2nπ and phase at any trough is (2n + 1)π, where n is an integer.
iii. It always travels in the forward direction. During the propagation of spherical wavefront from a source, wave becomes weaker. It is so because same energy is distributed over circumference of larger circles of increasing radii.
iv. In anisotropic medium, it travels with different velocities in different directions due to variation in densities of the medium.
