Advertisements
Advertisements
प्रश्न
The intensity of the light coming from one of the slits in Young's experiment is twice the intensity of the light coming from the other slit. What will be the approximate ratio of the intensities of the bright and dark fringes in the resulting interference pattern?
Advertisements
उत्तर
Data: I1 : I2 = 2 : 1
If E10 and E20 are the amplitudes of the interfering waves, the ratio of the maximum intensity to the minimum intensity in the fringe system is
`("I"_"max")/("I"_"min") = (("E"_10 + "E"_20)/("E"_10 - "E"_20))^2 = (("r + 1")/("r - 1"))^2`
where r = `"E"_10/"E"_20`
∴ `"I"_1/"I"_2 = (("E"_10)/("E"_20))^2 = "r"^2`
∴ r = `sqrt("I"_1/"I"_2) = sqrt2`
∴ `("I"_"max")/("I"_"min") = ((sqrt2 + 1)/(sqrt2 - 1))^2 = (2.414/0.414)^2 = (5.83)^2`
= 33.99 ≈ 34.
∴ The ratio of the intensities of the bright and dark fringes in the resulting interference pattern is 34: 1.
APPEARS IN
संबंधित प्रश्न
Laser light of wavelength 630 nm is incident on a pair of slits which are separated by 1.8 mm. If the screen is kept 80 cm away from the two slits, calculate:
1) fringe separation i.e. fringe width.
2) distance of 10th bright fringe from the centre of the interference pattern
When a drop of oil is spread on a water surface, it displays beautiful colours in daylight because of ______________ .
A long narrow horizontal slit is paced 1 mm above a horizontal plane mirror. The interference between the light coming directly from the slit and that after reflection is seen on a screen 1.0 m away from the slit. If the mirror reflects only 64% of the light energy falling on it, what will be the ratio of the maximum to the minimum intensity in the interference pattern observed on the screen?
The intensity at the central maximum (O) in a 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 equal `(I_0)/4`.
In Young’s double slit experiment, the slits are separated by 0.5 mm and 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.
What is meant by coherent sources?
Why two light sources must be of equal intensity to obtain a well-defined interference pattern?
Explain constructive and destructive interference with the help of a diagram?
How do source and images behave as coherent sources?
Explain Young’s double-slit experimental setup and obtain the equation for path difference.
Discuss the interference in thin films and obtain the equations for constructive and destructive interference for transmitted and reflected light.
In Young's double-slit experiment, in an interference pattern, a second minimum is observed exactly in front of one slit. The distance between the two coherent sources is 'd' and the distance between source and screen is 'D'. The wavelength of the light source used is ______
A metal rod has length, cross-sectional area and Young's modulus as L, A and Y, respectively. If the elongation in the rod produced is l, then work done is proportional to ______.
The light waves from two independent monochromatic light sources are given by, y1 = 2 sin ωt and y2 = 3 cos ωt. Then the correct statement is ____________.
Two identical light waves having phase difference 'Φ' propagate in same direction. When they superpose, the intensity of the resultant wave is proportional to ______.
In Young's experiment, the distance between the slits is doubled and the distance between the slit and screen is reduced to half, then the fringe width ____________.
A thin mica sheet of thickness 4 x 10-6 m and refractive index 1.5 is introduced in the path of the first wave. The wavelength of the wave used is 5000 A. The central bright maximum will shift ______.
In Young's double-slit experiment, an interference pattern is obtained on a screen by a light of wavelength 4000 Å, coming from the coherent sources S1 and S2 At certain point P on the screen, third dark fringe is formed. Then the path difference S1P - S2P in microns is ______.
In Young's double slit experiment, the two slits act as coherent sources of equal amplitude A and wavelength `lambda`. In another experiment with the same set up the two slits are of equal amplitude A and wavelength `lambda`. but are incoherent. The ratio of the intensity of light at the mid-point of the screen in the first case to that in the second case is ____________.
The phenomenon of interference is based on ______.
In biprism experiment, the 4th dark band is formed opposite to one of the slits. The wavelength of light used is ______.
If the two slits in Young's double slit experiment have width ratio 9 : 1, the ratio of maximum to minimum intensity in the interference pattern is ______.
In biprism experiment, if the 5th bright band with wavelength 'λ1' coincides with the 6th dark band with wavelength 'λ2' then the ratio `(lambda_2/lambda_1)` is ______
In a biprism experiment, monochromatic light of wavelength (λ) is used. The distance between two coherent sources is kept constant. If the distance between slit and eyepiece (D) is varied as D1, D2, D3, and D4, the corresponding measured fringe widths are z1, z2, z3, and z4 then ______
In the biprism experiment, a source of monochromatic light is used for a certain distance between slit and eyepiece. When the distance between two virtual sources is changed from dA to dB, then the fringe width is changed from ZA to ZB. The ratio ZA to ZB is ______
Two coherent sources of intensities I1 and I2 produce an interference pattern on the screen. The maximum intensity in the interference pattern is ______
A beam of electrons is used in Young's double-slit experiment. If the speed of electrons is increased then the fringe width will ______.
