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प्रश्न
In Fraunhofer diffraction, how is the angular width of the central bright fringe affected when slit separation is increased?
उत्तर
In Fraunhofer diffraction at a single slit, we obtain a central bright band, having on both sides narrower
alternately dark and bright bands of decreasing intensity. Finer the slit, broader is the diffraction pattern and wider is the central band as shown in the given figure.
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संबंधित प्रश्न
What is 'diffraction of light'
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.
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.
Explain two types of diffraction of light.
Two wavelengths of sodium light 590 nm and 596 nm are used, in turn, to study the diffraction taking place due to a single slit of aperture 1 × 10−4 m. The distance between the slit and the screen is 1.8 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° ?
Which of the following device is used to study the spectra of light?
Consider the diffraction pattern for a small pinhole. As the size of the hole is increased ______.
- the size decreases.
- the intensity increases.
- the size increases.
- the intensity decreases.
In a diffraction pattern due to a single slit, how will the angular width of the central maximum change, if the slit width is decreased?
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 ______.
