Description : To observe interference in thin films with a light of wavelength λ, the thickness of the film (a) Should be much smaller than λ (b) Should be a few thousand times of λ (c) Should be of the order of λ (d) Should be of the order of nanometer
Last Answer : (c) Should be of the order of λ
Description : Why in Newton’s rings the center spot is always dark? A. The thickness of the film is zero at center B. The path difference between incident ray and reflected ray is ½wavelength C. The incident ray and reflected ray undergo destructive interference D. All of above
Last Answer : D. All of above
Description : The conditions for the production of constructive and destructive interference are reversed due to the fact that on striking the thin film -------. A. Two rays of splitted light undergo phase ... two rays of splitted light undergo phase change of 180° C. Light is diffracted, light is polarized
Last Answer : A. Two rays of splitted light undergo phase change of 180°
Description : On a rainy day, small oil films on water show brilliant colors'. This is due to A. dispersion B. interference C. diffraction D. Polarization 49.The critical angle for a beam of light ... A. absorbed B. totally reflected C. Partially reflected and partially transmitted D. Totally transmitted
Last Answer : C. Partially reflected and partially transmitted
Description : A thin film having thickness t
Last Answer : (c) Black
Last Answer : C. Black
Description : Colors in thin films are because of A. Dispersion C. Interference B. Compton effect D. Diffraction
Last Answer : C. Interference
Description : When a light wave suffers reflection at the interface between air and glass medium, the change of wavelength of the reflected wave in air is equal to (a) 0 (b) λ/2 (c) λ (d) 2λ
Last Answer : (b) λ/2
Description : If you look perpendicular at thin film and move yourself away from the film (staying perpendicular to the film), you will notice (a) Reflected light becomes brighter and brighter (b) Reflected ... and darker (c) Reflected light alternates between darker and brighter (d) None of the Above
Last Answer : (c) Reflected light alternates between darker and brighter
Description : In Michelson interferometer semi silvered mirror is used To obtain __________. A. Thin film interference B. Phase coherence C. mono chromatic light D. colored fringe
Last Answer : B. Phase coherence
Description : Interference in thin film is mainly because of (a) Division amplitude (b) Division of wave fronts (c) Addition of amplitude (d) Addition of wave fronts
Last Answer : (a) Division amplitude
Description : Interference in thin film is mainly because of A. Division amplitude B. Division of wave fronts C. Addition of amplitude D. Addition of wave fronts
Last Answer : A. Division amplitude
Description : In case of thin film of non-uniform thickness, when illuminated with white light, the film appears colored. This is due to change of what factor? (a) Conditions for path difference at different points of ... of film (c) Thickness of film is different at different points of film (d) All of above
Last Answer : (d) All of above
Description : Newton's rings are formed because of interference between the light Reflected from (a) Upper surface of Plano-convex lens and lower surface of plane glass plate (b) Lower surface of Plano-convex ... c) Lower and upper surface of Plano-convex (d) Lower and upper surfaces of plane glass plate
Last Answer : (b) Lower surface of Plano-convex lens and upper surface of plane glass plate
Description : Interference pattern is observed in wedge-shaped film and bandwidth is noted. Now the thin film is replaced by the film of higher refractive index. What will be the effect on bandwidth? (a) Bandwidth increases (b) Bandwidth decreases (c) Bands will merge (d) There will not any effect
Last Answer : (b) Bandwidth decreases
Description : What is the nature of interference pattern for thin film of wedge shaped (a) Concave outside (b) Convex outside (b) Equally spaced (d) Concave inside
Last Answer : (b) Convex outside
Description : In interference experiment, by keeping all other parameters constant, if you see the thin film interference from different angles, you will observe (a)Uniform illumination of screen (b) Uniform ... c) Equally spaced dark and white bands (d) Few colored bands and then general illumination
Last Answer : (d) Few colored bands and then general illumination
Description : What is the nature of interference pattern for thin film of wedge shaped A. Concave outside B. Convex outside C. Equally spaced D. Concave inside
Last Answer : B. Convex outside
Description : When Newton’s rings interference pattern is viewed from above by means of reflected light, the central spot is __________. A. Dark B. Multi colored C. Bright D. None of these
Last Answer : A. Dark
Description : The path difference corresponding to a phase difference of π radian is __________. A.2λ B .λ/2 C .λ /4 D. λ
Last Answer : B .λ/2
Description : When a light ray travelling in glass is incident on an air surface, A. it will refract away from the normal B. some of the light may be reflected C. all of the light may be reflected D. two of A, B, and C E. all of A, B, and C
Last Answer : E. all of A, B, and C
Description : Interference pattern is observed in wedge-shaped film for monochromatic light. Now monochromatic light is replaced by white light. What will be the effect on interference pattern? (a) It will turn to dark (b) It will turn to bright (c) Bands will disappear (d) It will be a mixture of all colors
Last Answer : (d) It will be a mixture of all colors
Description : What is the nature of interference pattern at the contact edge of wedge shaped film (a) Always bright (b) Always dark (c) Bright or dark depending upon the thickness of other end (d) Bright or dark depending upon the wavelength of the light
Last Answer : (b) Always dark
Description : A thin film is observed in white light. The color of the film seen at a particular point depends upon (a)Location of observer (b)Width of the source (c) Distance of the source (d) Brightness of the source
Last Answer : (a)Location of observer
Description : A film is said to be thin if its thickness is (a) Much smaller than wavelength of light (b) Comparable with one wavelength of light (c) Of the order of nanometer (10-9 m) (d) Of the order of Pico meter (10-12 m)
Last Answer : (b) Comparable with one wavelength of light
Description : .In Rayleigh law of scattering ,The intensity of scattered light is proportional to A. λ B. λ -2 C. λ -4 D. λ-1
Last Answer : C. λ -4
Description : Interference pattern is observed in wedge-shaped film and bandwidth is noted. Now the angle of wedge is reduced to zero. What will be the effect on Bandwidth? (a) Bandwidth increases (b) Bandwidth decreases (c) Bands will disappear (d) There will not any effect
Last Answer : (c) Bands will disappear
Description : Interference pattern is observed in wedge-shaped film and bandwidth is noted. Now the angle of wedge is reduced. What will be the effect on bandwidth? (a) Bandwidth increases (b) Bandwidth decreases (c) Bands will disappear (d) There will not any effect
Last Answer : B) BANDWIDTH DECREASES
Description : In wedge shaped film the interference pattern has nature (a) Parallel to the end where thickness is non-zero (b) Perpendicular to contact edge (c) Parallel to contact edge (d) Perpendicular to the end where thickness is non-zero
Last Answer : (c) Parallel to contact edge
Description : When a light wave suffers reflection at the interface between air and glass medium, the change of phase of the reflected wave in air is equal to (a) 0 (b) π (c) 2π (d) π/2
Last Answer : (b) π
Description : When a light wave suffers reflection at the interface between air and glass medium, the change of phase of the reflected wave in air is equal to A. 0 B. π C.2 π D.π /2
Last Answer : B. π
Description : Light is normally incident on a thin soap film and is reflected. If the wavelength of this light is "L" and the index of refraction of the soap film is "N", complete destructive interference will occur for a film thickness of: w) L / 8N x) L / 4N y) L / 2N z) 3L / 4N
Last Answer : ANSWER: Y -- L / 2N
Description : Resolving power of grating is given by A. λ/2 B. λ/dλ C. dλ/λ D. none of these
Last Answer : B. λ/dλ
Description : The fringe width and the angle of wedge are related to A. β=λ/2θ B. θ =λ/2 β C. β=λ/θ D. λ= β/2θ
Last Answer : A. β=λ/2θ
Description : In reflected light the central fringes of Newton's ring is A. dark B. Bright C. Uniform D. Non uniform
Last Answer : A. dark
Description : Newton’s light illustrate the phenomenon of (a) Interference (b) Diffraction (c) Dispersion (d) Polarisation
Last Answer : (a) Interference
Description : In interference experiment, monochromatic light is replaced by white light, we will see (a) Uniform illumination of screen (b) Uniform darkness on the screen (c) Equally spaced dark and white bands (d) Few colored bands and then general illumination
Description : __________ of the following phenomenon cannot be explained on the particle nature of light. A. Photo Electric Effect B. Compton’s Effect C. Pair Production D. Interference
Last Answer : A. Photo Electric Effect
Description : The points of constructive interference of light are__________. A. Always bright B. may be bright or dark C. always dark D. neither bright nor dark
Last Answer : A. Always bright
Description : Which of the following does not support the wave nature of light A. Interference C. Polarisation B. Compton effect D. Diffraction
Last Answer : B. Compton effec
Description : Interference of light is evidence that : A. The speed of light is very large B. light is a transverse wave C. light is electromagnetic in character D. Light is a wave phenomenon
Last Answer : D. Light is a wave phenomenon
Description : .Light is A. an electromagnetic wave B. a form of energy visible to the human eye C. the same type of energy as an X ray D. the same type of energy as a radio wave E. all of the above
Last Answer : E. all of the above
Description : In Fraunhofer diffraction pattern for single slit, a central maximum is obtained when angle of diffraction q is equal to zero. What it actually indicates? A. All the diffracted rays are parallel and focused ... are diffracted by the slit in all the directions D. The rays are reflected by the slit
Last Answer : A. All the diffracted rays are parallel and focused by slit at a single point on screen
Description : When electromagnetic waves strike the boundary of denser medium they are __________. A. Reflected, in phase B. Reflected out of phase by 180° C. reflected, they are completely absorbed
Last Answer : B. Reflected out of phase by 180°
Description : It is the angle at which the propagating ray strikes the interface with respect to the normal. ∙ A. refracted angle ∙ B. incident angle ∙ C. reflected angle ∙ D. critical angle
Last Answer : incident angle
Description : Which of the following phenomenon produces colors in soap bubble? (a) Interference (b) Diffraction (c) Polarization (d) Dispersion
Description : Diffraction is special type of __________. A. Reflection B. Refraction C. Interference D. Polarization
Last Answer : B. Refraction
Description : Optical fiber works on the A. principle of refraction B. total internal reflection C. scattering D. interference
Last Answer : B. total internal reflection
Description : hat is the name of the process whereby waves travel around corners and obstacles in their paths? A. Reflection B. Refraction C Interference D. Diffraction
Last Answer : D. Diffraction
Description : In reference with antireflection coating which of the following statement is true? A. Thickness of the film should be changed for light of same wavelength but different intensity B. Thickness of ... D. Thickness of the film should be decreased for light of same wavelength but higher intensity
Last Answer : B. Thickness of the film need not be changed for light of same wavelength but different intensity