What is the shape of the wavefront in each of the following cases: (a) Light diverging from a point source.(b) Light emerging out of a convex lens when a point source is placed at its focus.(c) The portion of the wavefront of light from a distant star intercepted by the Earth.
(a) The point source emits the spherical wavefront as the light diverges from a point source in all directions.
(b) Plane. The shape of the wavefront in case of a light emerging out of a convex lens when a point source is placed at its focus is a parallel grid.
(c) Plane (a small area on the surface of a large sphere is nearly planar). The portion of the wavefront of light from a distant star intercepted by the Earth is a plane.
An initially parallel cylindrical beam travels in a medium of refractive index $$\mu(I) =\mu_0 + \mu_2 I$$, where $$\mu_0$$ and $$\mu_2$$ are positive constants and $$I$$ is the intensity of the light beam. The intensity of the beam is decreasing with increasing radius. The initial shape of the wave front of the beam is
The phenomena which is not explained by Huygen's construction of the wavefront
which one of the following phenomenon is not explained by Huygen's construction of wavefront
Ray diverging from a point source form a wave front that is
A plane wave front falls on a convex lens. The emergent wave front:
Wave front formed by the collimator of a spectrometer
For the situation shown in the figure below. $$BP - AP = \dfrac {\lambda}{3}$$ and $$D > > d$$. The slits are of equal widths, having intensity $$I_{0}$$. The intensity at $$P$$ would be :