Advertisements
Advertisements
प्रश्न
State Huygens’s principle. Show, with the help of a suitable diagram, how this principle is used to obtain the diffraction pattern by a single slit.
Draw a plot of intensity distribution and explain clearly why the secondary maxima becomes weaker with increasing order (n) of the secondary maxima.
Advertisements
उत्तर
Huygen’s principle states that
-
Each point on a wave front behaves as a source of secondary wavelets
-
The secondary wavelets travel with the speed of light in that medium
-
The position of new wave front at a later time can be found out by drawing a common tangent to all these secondary wavelets
Intensity distribution of single slit distribution
For the first secondary maxima (n = 1), only one-third of the slit contributes to its intensity.
Secondly, for n = 2, only one-fifth of the slit contributes to the intensity.
Therefore, with increasing n, the intensity decreases.
APPEARS IN
संबंधित प्रश्न
Using Huygens's construction of secondary wavelets explain how a diffraction pattern is obtained on a screen due to a narrow slit on which a monochromatic beam of light is incident normally.
What is the shape of the wavefront in the following case?
Light emerging out of a convex lens when a point source is placed at its focus.
What is the shape of the wavefront in the following case?
The portion of the wavefront of light from a distant star was intercepted by the Earth.
The refractive indices of water and diamond are `4/3` and 2.42 respectively. Find the speed of light in water and diamond. (c = 3x108 m/s)
When the width of the slit is made double the original width, how would this affect the size and intensity of the central diffraction band?
Define the term wavefront. Using Huygen’s wave theory, verify the law of reflection.
A plane wave front AB propagating from denser medium (1) into a rarer medium (2) is incident on the surface P1P2 separating the two media as shown in fig.
Using Huygen’s principle, draw the secondary wavelets and obtain the refracted wave front in the diagram.
Is Huygen’s principle valid for longitudinal sound waves?
What type of wavefronts are associated with a source infinity?
What type of wavefronts are associated with a point source of light?
