2025 Exam Questions
Q. What is Brewster’s law? Derive the formula for Brewster’s angle.
Q. Distinguish between interference and diffraction of light.
Q. A double slit arrangement produces interference fringes for sodium light of wavelength 589 nm , that are 0.20 degree apart. What is the angular fringe separation if the entire arrangement is immersed in water? (R.I. of water =1.33)
2024 Exam Questions
Q. In biprism experiment, the distance of 20th bright band fromt he central bright band is 1.2 cm. Without changing the experimental set-up, the distance of 30th bright band from the central bright band will be ____.
(a) 0.6 cm
(b) 0.8 cm
(c) 1.2 cm
(d) 1.8 cm
Q. Explain the construction of spherical wavefront by using Huygen’s principle.
Q. Using the geometry of the double slit experiment, derive the expression for fringe width of interference bands.
2023 Exam Questions
Q. The property of light which remains unchanged when it travels from one medium to another is ____.
(A) velocity
(B) wavelength
(C) amplitude
(D) frequency
Q. Derive the laws of reflection of light using Huygens’ principle.
Q. In a biprism experiment, the fringes are observed in the focal plane of the eye-piece at a distance of 1.2 m from the slit. The distance between the central bright band and the 20th bright band is 0.4 cm. When a convex lens is placed between the biprism and the eye-piece, 90 cm from the eye-piece, the distance between the two virtual magnified images is found to be 0.9 cm. Determine the wavelength of light used.
2022 Exam Questions
Q. In Young’s double slit experiment the two coherent sources have different amplitudes. If the ratio of maximum intensity to minimum intensity is 16 : 1, then the ratio of amplitudes of the two source will be ____.
(A) 4 : 1
(B) 5 : 3
(C) 1 : 4
(D) 1 : 16
Q. What changes are observed in a diffreaction pattern if the whole apparatus is immersed in water?
(A) the wavelength of light increases
(B) width of central maximum increases
(C) width of central maximum decreases
(D) frequency of light decreases
Q. The property of light which remains unchanged when it travels from one medium to another is ____.
(A) velocity
(B) wavelength
(C) amplitude
(D) frequency
Q. Derive the laws of reflection of light using Huygens’ principle.
Q. With the help of a neat diagram, explain the reflection of light on a plane reflecting surface.
Q. What happens to the frings width in diffraction pattern if the diameter of wire is increased?
Q. Plane wavefront of light of wavelength 6000\;\overset oA is incident on two slits on a screen perpendicular to the direction of light rays. If the total separation of 10 bright frings on a screen 2 m away is 2 cm, find the distance between the slits.
Q. A plane wavefront of light of wavelength 4000\;\overset oA is incident on two slits on a screen perpendicular to the direction of light ray. If the total separation of 10 bright fringes on a screen 2 m away is 2 cm, find the distance between the slits.
