हिंदी

Explain Two Types Of Diffraction of Light. - Physics

Advertisements
Advertisements

प्रश्न

Explain two types of diffraction of light.

उत्तर

The diffraction phenomenon is classified into two types:
1. Fraunhofer diffraction: The source of light and the screen on which the diffraction pattern is obtained are effectively at infinite distance from the diffracting system. In this case, we consider plane wavefront. The diffraction pattern is obtained by using a convex lens.
2. Fresnel diffraction: The source of light and the screen are kept at finite distance from the diffracting system. In this case, we consider a cylindrical or spherical wavefront.

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
2015-2016 (March)

APPEARS IN

वीडियो ट्यूटोरियलVIEW ALL [2]

संबंधित प्रश्न

In a single slit diffraction pattern, the distance between first minima on the right and first minima on the left of central maximum is 4 mm. The screen on which the pattern is displaced, is 2m from the slit and wavelength of light used is 6000Å. Calculate width of the slit and width of the central maximum.


Explain why the maxima at `theta=(n+1/2)lambda/a` become weaker and weaker with increasing n


For a single slit of width "a", the first minimum of the interference pattern of a monochromatic light of wavelength λ occurs at an angle of λa. At the same angle of λa, we get a maximum for two narrow slits separated by a distance "a". Explain.


Describe briefly how a diffraction pattern is obtained on a screen due to a single narrow slit illuminated by a monochromatic source of light. Hence obtain the conditions for the angular width of secondary maxima and secondary minima.


Two wavelengths of sodium light of 590 nm and 596 nm are used in turn to study the diffraction taking place at a single slit of aperture 2 × 10−6 m. The distance between the slit and the screen is 1·5 m. Calculate the separation between the positions of first maxima of the diffraction pattern obtained in the two cases.


In Fraunhofer diffraction, how is the angular width of the central bright fringe affected when slit separation is increased?


Draw the intensity distribution for the diffraction bands produced due to single slit ?


Two wavelengths of sodium light 590 nm and 596 nm are used, in turn to study the diffraction taking place at a single slit of aperture 2 × 10−4m. The distance between the slit and the screen is 1.5 m. Calculate the separation between the positions of the first maxima of the diffraction pattern obtained in the two cases.


Monochromatic light of wavelength 4300 Å falls on a slit of width ‘a’. For what value of ‘a’ the first maximum falls at 30° ?


Wavelength of light of frequency 100 Hz is


The penetration of light into the region of geomaterial shadow is called.


Diffraction effects are easy to notice in the case of sound waves than in case of light waves because


Direction of the first secondary maximum in the Fraunhoffer diffraction pattern at a single slit is given by (a is the width of the slit):


Consider the diffraction pattern for a small pinhole. As the size of the hole is increased ______.

  1. the size decreases.
  2. the intensity increases.
  3. the size increases.
  4. the intensity decreases.


AC = CO = D, S1C = S2C = d << D

A small transparent slab containing material of µ = 1.5 is placed along AS2 (Figure). What will be the distance from O of the principal maxima and of the first minima on either side of the principal maxima obtained in the absence of the glass slab?


How can you differentiate whether a pattern is produced by a single slit or double slit?


Derive the expression for the angular position of (i) bright and (ii) dark fringes produced in a single slit diffraction.


In a diffraction pattern due to a single slit, how will the angular width of the central maximum change, if the screen is moved closer to the slit?

Justify your answer.


In the diagram shown, the separation between the slit is equal to 3λ, where λ is the wavelength of the light incident on the plane of the slits. A thin film of thickness 3λ and refractive index 2 has been placed in the front of the upper slit. The distance of the central maxima on the screen from O is ______.

 


In a single slit Fraunhofer diffraction experiment, how does the angular width of the central maximum change when the slit width is Increased?


Draw a labelled graph showing the variation in intensity of diffracted light with diffracting angle in a single slit Fraunhofer diffraction experiment.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×