Spherical wavefronts,as shown in the figure,strike a plane mirror. The reflected wavefront will be as shown in:

When light propagates through a given homogeneous medium,the velocities of

Consider a point at the focal point of a convergent lens. Another convergent lens of short focal length is placed on the other side. What is the nature of the wavefronts emerging from the final image?

On a hot summer night,the refractive index of air is smallest near the ground and increases with height from the ground. When a light beam is directed horizontally,the Huygens' principle leads us to conclude that as it travels,the light beam

Given below are two statements:
Statement-$I$: $A$ plane wave after passing through a prism remains a plane wave, but passing through a small pinhole may become a spherical wave.
Statement-$II$: The curvature of a spherical wave emerging from a slit will increase for increasing slit width.
In the light of the above statements, choose the correct answer from the options given below.

Derive the laws of refraction using the concept of Huygens' principle of wavefronts.