Two slits separated by a distance of 1 mm, are illuminated with red light of wavelength 6.5 x 10-7 m. The interference fringes are observed on a screen placed 1 m from the slits. Find the distance (in mm) between the third dark fringe and the fifth bright fringe on the same side of the central maxima.
Hence we can use
So distance between 5th bright fringe and 3rd dark fringe
= 1.625 mm
The correct answer is: 1.625
The path difference between two interfering waves at a point on the screen is λ/6. The ratio of intensity at this point and that at the central bright fringe will be : (Assume that intensity due to each slit in same)
At path difference phase difference is
So the required ratio is
The correct answer is: 0.75
If the distance between the first maxima and fifth minima of a double slit pattern is 7 mm and the slits are separated by 0.15 mm with the screen 50 cm from the slits, then wavelength (in nm) of the light used is :
There are three and a half fringes from first maxima to fifth minima as shown
The correct answer is: 600
Calculate the width (in mm) of central maxima. If light of 9000 A incidents upon a slit of width 1.5 mm. Screen is kept 150 cm away from the slit.
Width of central maxima
The correct answer is: 1.8
If the ratio of the intensity of two coherent sources is 4, then the visibility of the fringes is.
The correct answer is: 0.8
If the relative permitivity and relative permeability of a medium are 2 & 1.28 respectively, then refractive index of the material is.
The correct answer is: 1.6
Two lightwaves are given by and The ratio intensity of first wave to that of second wave is.
The correct answer is: 0.444
A light ray incidents on water surface from air and reflected part of it is found to be polarized. Find the deviation (in degrees) of refracted light from its original path :
The correct answer is: 16
In young’s double slit experiment, we get 60 fringes in the field of view of monochromatic light of wavelength 4000 . If we use monochromatic light of wavelength 6000 , then the number of fringes that would be obtained in the same field of view is.
λ α (Fringe width)
Higher 'λ' means wider fringes.
At higher wavelength, same space on the screen is occupied by wider fringes, and hence lesser number of fringes.
The correct answer is: 40
A single slits of width 0.1 mm is illuminated by parallel light of wavelength 6000 and diffraction bands are observed on a screen 40 cm from the slit. The distance (in mm) of third dark band from the central bright band is :
The correct answer is: 7.2