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प्रश्न
Which of the following sources provides the best monochromatic light?
विकल्प
A candle
A bulb
A mercury tube
A laser
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उत्तर
A laser
Among the given sources, laser is the best coherent source providing monochromatic light with constant phase difference.
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संबंधित प्रश्न
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When light travels from a rarer to a denser medium, the speed decreases. Does this decrease in speed imply a reduction in the energy carried by the wave?
What kind of fringes do you expect to observe if white light is used instead of monochromatic light?
State the essential conditions for diffraction of light ?
When monochromatic light travels from a rarer to a denser medium, explain the following, giving reasons:
(i) Is the frequency of reflected and refracted light same as the frequency of incident light?
(ii) Does the decrease in speed imply a reduction in the energy carried by light wave?
State Huygen’s principle. Using this principle explain how a diffraction pattern is obtained on a screen due to a narrow slit on which a narrow beam coming from a `=> n = (vlamda)/(vlamda_omega)`monochromatic source of light is incident normally.
Consider the situation shown in the figure. The two slits S1 and S2 placed symmetrically around the central line are illuminated by a monochromatic light of wavelength λ. The separation between the slits is d. The light transmitted by the slits falls on a screen ∑1placed at a distance D from the slits. The slit S3 is at the central line and the slit S4 is at a distance z from S3. Another screen ∑2 is placed a further distance D away from ∑1.Find the ratio of the maximum to minimum intensity observed on ∑2 if z is equal to
(a) \[z = \frac{\lambda D}{2d}\]
(b) \[\frac{\lambda D}{d}\]
(c) \[\frac{\lambda D}{4d}\]
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Monochromatic light of wavelength 650 nm falls normally on a slit of width 1 : 3 × 10-4 cm and the resulting Fraunhofer diffraction is obtained on a screen. Find the angular width of the central maxima.
Find the angle of incidence at which a ray of monochromatic light should be incident on the first surface AB of a regular glass prism ABC so that the emergent ray grazes the adjacent surface AC. (Refractive Index of glass = 1 .56)
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Answer the following question.
In the diffraction due to a single slit experiment, the aperture of the slit is 3 mm. If monochromatic light of wavelength 620 nm is incident normally on the slit, calculate the separation between the first order minima and the 3rd order maxima on one side of the screen. The distance between the slit and the screen is 1.5 m.
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(b) The intensity at the central maximum (O) in Young's double-slit experimental set-up shown in the figure is IO. If the distance OP equals one-third of the fringe width of the pattern, show that the intensity at point P, would `"I"_°/4`
(c) In Young's double-slit experiment, the slits are separated by 0⋅5 mm and the screen is placed 1⋅0 m away from the slit. It is found that the 5th bright fringe is at a distance of 4⋅13 mm from the 2nd dark fringe. Find the wavelength of light used.
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A ray of monochromatic light propagating in the air is incident on the surface of the water. Which of the following will be the same for the reflected and refracted rays?
Monochromatic light of wavelength 396 nm is incident on the surface of a metal whose work function is 1.125 eV. Calculate:
- the energy of an incident photon in eV.
- the maximum kinetic energy of photoelectrons in eV.
The Figure below shows a ray of monochromatic light LM incident on the first surface AB of a regular (equilateral) glass prism ABC. The emergent ray grazes the adjacent surface AC. Calculate the angle of incidence. (Refractive Index of glass = 1.5)
