Advertisements
Advertisements
प्रश्न
Figure shows a standard two slit arrangement with slits S1, S2, P1, P2 are the two minima points on either side of P (Figure). At P2 on the screen, there is a hole and behind P2 is a second 2-slit arrangement with slits S3, S4 and a second screen behind them.
विकल्प
There would be no interference pattern on the second screen but it would be lighted.
The second screen would be totally dark.
There would be a single bright point on the second screen.
There would be a regular two slit pattern on the second screen.
Advertisements
उत्तर
There would be a regular two slit pattern on the second screen.
Explanation:
Every point on the given wave front acts as a source of new disturbance called secondary wavelets which travel in all directions with the velocity of light in the medium.
A surface touching these secondary wavelets tangentially in the forward direction at any instant gives the new wavefront at that instant. This is called secondary wavefront. In the given question, there is a hole at point which is a maxima point. From Huygen’s principle, wave will propagate from the sources S1 and S2. Each point on the screen will act as secondary source of wavelets.
The wavefront emitted by a narrow source is divided into two parts reflection, refraction or diffraction. The coherent sources so obtained are imaginary.
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.
Explain the construction of plane wavefront using Huygens’ principle.
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.
You have learnt in the text how Huygens’ principle leads to the laws of reflection and refraction. Use the same principle to deduce directly that a point object placed in front of a plane mirror produces a virtual image whose distance from the mirror is equal to the object distance from the mirror.
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)
Using this principle draw a diagram to show how a plane wave front incident at the interface of the two media gets refracted when it propagates from a rarer to a denser medium. Hence verify Snell's law of refraction.
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?
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.
Light waves travel in vacuum along the X-axis. Which of the following may represent the wave fronts?
Derive the law of reflection using Huygen’s Wave Theory.
Define a wavefront. Using 'Huygens' principle, draw the shape of a refracted wavefront, when a plane wave is incident on a convex lens.
Relation between ray and wavefront is ______.
What is the geometrical shape of the wavefront for:
- Light diverging from a point source?
- The pattern of wavefront of the light from a distant star intercepted by earth?
The inverse square law of intensity is valid for a
For light diverging from a point source ______.
- the wavefront is spherical.
- the intensity decreases in proportion to the distance squared.
- the wavefront is parabolic.
- the intensity at the wavefront does not depend on the distance.
Two light beams of intensities in the ratio of 9 : 4 are allowed to interfere. The ratio of the intensity of maxima and minima ______.
How is a wavefront different from a ray?
Represent diagrammatically how the incident planar wavefronts of wavelength λ pass through an aperture of size d, when d is approximately equal to λ.
