Two coherent sources have intensity ratio of 100:1, and are used for obtaining the phenomenon of interference. Then the ratio of maximum and minimum intensity will be-
1. 100:1
2. 121:81
3. 1:1
4. 5:1
In young's double slit experiment 62 fringes are visible in the field of view with sodium light . If green light is used then the number of visible fringes will be-
1. 62
2. 67
3. 85
4. 58
If the yellow light is replaced by the violet light then the interference fringes-
1. Will become fainter
2. Will become brighter
3. The fringe width will increase
4. The fringe width will decrease
In a YDSE, the central bright fringe can be identified.
1. as it has greater intensity than the other bright fringes.
2. as it is wider than the other bright fringes
3. as it is narrower than the other bright fringes
4. by using white light instead of single wavelength light.
Two identical narrow slits are illuminated by light of wavelength from a point source P. If, as shown in the diagram below the light is then allowed to fall on a screen, and if n is a positive integer, the condition for destructive interference at Q is that
In a young double slit experiment D equals the distance of screen from slits and d is the seperation between the slits. The distance of the nearest point to the central maximum where the intensity is same as that due to a single slit, is equal to
1.
2.
3.
4.
In a young's Double slit experiment, first maxima is observed at a fixed point P on the screen. Now the screen is continously moved away from the plane of slits. The ratio of intensity at point P to the intensity at point O (centre of the screen)
1. remains constant
2. keeps on decreasing
3. first decreases and then increases
4. First decreases and then becomes constant
In a double slit experiment, the seperation between the slits is d=0.23 cm and the distance of the screen D=100 cm from the slits. If the wavelength of light used is =6000 and is the intensity of the central bright fringe, the intensity at a distance x= m from the central maximum is
1.
2.
3.
4.
Two slits are seperated by 0.3 mm. A beam of 500 nm light strikes the slits producing an interference pattern. The number of maxima observed in the angular range
1. 300
2. 150
3. 601
4. 149
Light of wavelength in air enters a medium of refractive index . Two points in this medium, lying along the path of this light, are at a distance x apart. The phase difference between these points is:
Minimum thickness of a mica sheet having which should be placed in front of one of the slits in YDSE to reduce the intensity at the centre of screen to half of maximum intensity is -
In young's double slit experiment, green light is incident on the two slits. The interference pattern is observed on a screen. Which of the following changes would cause the observed fringes to be more closely spaced?
1. Reducing the seperation between the slits
2. Using blue light instead of green light
3. Used red light instead of green light
4. Moving the light source further away from slits
In a YDSE, if the slits are of unequal width.
1. fringes will not be formed
2. the positions of minimum intensity will not be completely dark
3. bright fringes will not be formed at the centre of the screen.
4. distance between two consecutive bright fringes will not be equal to the distance between two consecutive dark fringes.
Figure shown plane waves refracted from air to water using Huygen's principle and a, b, c, d, e are lengths on the diagram. The refractive index of water wrt air is -
1. a/e
2. b/e
3. b/d
4. d/b
Two point source seperated by d=5 emit light of wavelength =2 in phase. A circular wire of radius 20 is placed around the source as shown in figure.
1. Point A and B are dark and points C and D are bright
2. Points A and B are bright and point C and D are dark
3. Points A and C are dark and points B and D are bright
4. Points A and C are bright and points B and D are dark
In young's double slit experiment, the two slits act as coherent sources of equal amplitude A and wavelength . In another experiment with the same setup the two slits are sources of equal amplitude A and wavelength but are incoherent. The ratio of the average intensity of light at the midpoint of the screen in the first case so that in the second case is
1. 1:1
2. 2:1
3. 4:1
4. none of these
A beam of light consisting of two wavelengths 6500 and 5200 is used to obtain interference fringes in Young's double slit experiment. The distance between slits is 2mm and the distance of screen from slits is 120 cm. What is the least distance from central maximum where the bright fringes due to both wavelength coincide?
1. 0.156 cm
2. 0.312 cm
3. 0.078 cm
4. 0.468 cm