Description : In Fraunhofer diffraction wave front used is __________. A. Spherical B. Circular C. Plane D. Conical 71.In diffraction pattern of monochromatic light the bright bands formed are __________. A. of uniform intensity B. of non-uniform intensity C. of uniform width D. is of different colors
Last Answer : A. of uniform intensity
Description : The condition for minima in Fraunhofer diffraction for single slit is asinθ = mλWhat is ‘θ’? A. Angle of incidence of incident rays at the slit B. Angle at which diffracted rays strikes the screen C. Angle between slit and screen D. Angle of diffraction at which rays are diffracted at slit
Last Answer : D. Angle of diffraction at which rays are diffracted at slit
Description : Fraunhofer diffraction at a Plane Grating What is the meaning of grating element for a diffraction grating? A It is the width of a single slit B. It is the width of the opaque space C. It is the distance between two slits D. It is the width of diffraction grating
Last Answer : C. It is the distance between two slits
Description : How the intensity of secondary maxima varies in case of Fraunhofer diffraction pattern for single slit? A. Intensity of secondary maxima decreases on either sides B. Intensity of ... C. Intensity increases and decreases alternately D. Intensity of secondary maxima increases on either sides
Last Answer : A. Intensity of secondary maxima decreases on either sides
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 : Which of the following condition is essential for observing Fraunhofer diffraction? A. Source must be close to slit and screen should be at infinite distance B. Both source and screen must be close to ... infinity and screen should be close to the slit D. Both source and screen must be at infinity
Last Answer : D. Both source and screen must be at infinity
Description : here are two types of diffraction Fresnel and __________. A. Michelson B. De Broglie C. Fraunhofer D. Huygens
Last Answer : C. Fraunhofer
Description : Fraunhofer diffraction is observed when __________. A. Only screen is placed at finite distance B. source is placed at finite distance C. neither source nor screen is at finite distance D. None of these
Last Answer : D. None of these
Description : The phenomenon of diffraction can be understood using A. Huygens principle B. Fraunhofer C. Uncertainty principle D. Fresnel
Last Answer : A. Huygens principle
Description : The angle of incidence for a wave A. can be measured between the incident ray and the normal B. can be measured between the incident wave front and the boundary C. is equal to the angle of reflection D. all of the above
Last Answer : D. all of the above
Description : Diffraction due to circular aperture If a light passes through a small pinhole, and incident on a screen. What will be observed on the screen? A.A sharp bright point of the width equal to ... A bright ring at the centre surrounded by alternate dark and bright rings D. A diffused bright point
Last Answer : C. A bright ring at the centre surrounded by alternate dark and bright rings
Description : In plane transmission grating, the angle of diffraction for second order maxima for wavelength 5 x 10 -5 cm is 30 0. Calculate the number of lines in one centimeter of the grating surface. A. 1000 lines/cm B. 5000 lines/cm C. 500 lines/cm D. 10000 lines/cm
Last Answer : B. 5000 lines/cm
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 : The wave nature of light is demonstrated by which of the following? A. The photoelectric effect B. Color C. The speed of light D. Diffraction
Last Answer : D. Diffraction
Description : The dark lines constituting the absorption spectrum exhibited by sunlight are frequently called: A. Fresnel lines B. Fraunhofer lines C. Fermi lines D. Franklin lines
Last Answer : B. Fraunhofer lines
Description : Whose principle or law states that each point on a wave front may be considered a new wave source? Is it: A. Snell's Law B. Huygens’s Principle C. Young's Law D. Hertz's Law.
Last Answer : B. Huygens’s Principle
Description : Newton’s light illustrate the phenomenon of (a) Interference (b) Diffraction (c) Dispersion (d) Polarisation
Last Answer : (a) Interference
Description : Which of the following phenomenon produces colors in soap bubble? (a) Interference (b) Diffraction (c) Polarization (d) Dispersion
Description : What is the effect of increasing the number of slits on the intensity of Central maxima of diffraction pattern of a diffraction grating? A. Intensity of central maxima will decrease B. Intensity ... maxima will increase C. There will not be any effect D. Diffraction pattern will disappear
Last Answer : B. Intensity of central maxima will increase
Description : Diffraction is special type of __________. A. Reflection B. Refraction C. Interference D. Polarization
Last Answer : B. Refraction
Description : as the order increases, the width of a dark band in diffraction Patterns __________. A. Increases B. Decreases C. Does not change D. becomes infinity
Last Answer : Increases
Description : X-ray diffraction can be observed by using __________. A. Diffraction Grating B. Rock salt crystal C. Convex lens D. Michelson’s interferometer
Last Answer : A. Diffraction Grating
Description : .The grating used to observe, diffraction of visible light can have approximately __________. A.300 lines per cm B.3000 lines per cm, C. 15000 lines per cm D. 30 lines per cm
Last Answer : C. 15000 lines per cm
Description : The diffraction observed by diffraction grating can also be Termed as __________. A. Single slit diffraction B. double slit Diffraction C. multiple Slit Diffraction D. Fresnel’s Diffraction
Last Answer : A. Single slit diffraction
Description : Fresnel’s type diffraction is observed when __________. A. Only screen is placed at finite distance B. Only source is placed at finite distance C. Both source and screen are at finite distance D. Neither source nor screen is at finite distance
Last Answer : C. Both source and screen are at finite distance
Description : A diffraction grating is optically equivalent to a multiple slit system in which the number of slit , N is typically A.2000/cm B.3000/cm C.5000/cm D.1000/cm
Last Answer : C.5000/cm
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 : Colors in thin films are because of A. Dispersion C. Interference B. Compton effect D. Diffraction
Last Answer : C. Interference
Description : What is the highest order spectrum which may be seen with monochromatic light of wavelength 5000 A0by means of diffraction grating with 5000 lines/cm? A. 2 B. 4 C. 8 D. 16
Last Answer : B. 4
Description : To find prominent diffraction , the size of diffraction object should be A. greater than wavelength of light used B. comparable to order of wavelength of light C. less than wavelength of light used D. none of these.
Last Answer : B. comparable to order of wavelength of light
Description : In Fresnel diffraction A. source of light is kept at infinite distance from the aperture B. source of light is kept at finite distance from the aperture C. Convex lens used D. aperture width is selected so that it can acts as a point source
Last Answer : B. source of light is kept at finite distance from the aperture
Description : significant diffraction of X ray can be obtained A. By a single slit B. By a double slit C. By diffraction D. By Atomic crystal
Last Answer : A. By a single slit
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
Description : Why in Newton's rings setup, the beam splitter (mirror) is kept at 450? (a) It allows light rays to incident at 450over the top surface of Plano convex lens (b) It allows light rays to ... Plano convex lens (d) It allows light rays to incident at 900over the top surface of Plano convex lens
Last Answer : (d) It allows light rays to incident at 900over the top surface of Plano convex lens
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 : Coherent light of a single frequency passes through a double slit with a separation d, to produce a pattern on a screen as distance D from the slits. What would cause the separation between adjacent ... d between the slits C. increase the distance D. increase the frequency of the incident light
Last Answer : B. increase the separation d between the slits
Description : .A beam of light is incident on a large block of glass. The index of refraction of the glass is greater than one. Is the wavelength of the light in the glass? A. Longer than B. Shorter than C. The same as the wavelength of the light in the air? D. None of above
Last Answer : B. Shorter than
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 : 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 : The number of lines on plane gratings is 5000. If it is illuminated by a wavelength of light 6000 A0, how many orders will be visible? A. 3 B. 3.33 C. 4 D. 2.0
Last Answer : A. 3
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 : 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 : 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 : 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 : 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 : Two sources of light are said to be coherent if __________. A. they produce waves of the same wave length B. they have the same amplitude of vibration C. they produce waves in the medium simultaneously D. they produce waves of the same amplitude
Last Answer : D. they produce waves of the same amplitude
Description : The speed of any mechanical wave as it propagates through a medium is dependent mainly on the A. frequency of the wave source B. wavelength C. period of the wave D. type of medium through which the wave travels E. amplitude
Last Answer : D. type of medium through which the wave travels
Description : .As a wave travels down a spring, the amplitude slowly decreases. Why does this occur? A. The law of conservation of energy does not apply to waves. B. The energy is spread out along the entire ... due to friction as the particles in the spring rub against each other. E. all of the above
Last Answer : D. Some energy is lost due to friction as the particles in the spring rub against each other.
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 : 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