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 : .Fringe spacing is defined as the distance between two Consecutive __________. A. Crests B. Bright fringes only C. Dark fringes only D. Bright or dark fringes
Last Answer : A. Crests
Description : In Newton’s rings the central spot is __________. A. Always bright B. always dark C. can be bright or dark D. of blue color
Last Answer : C. can be bright or dark
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 : 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 Newton’s rings experiment, if we reduce the radius of curvature of Plano Convex lens to zero, what will be effect on Newton’s rings? (a)They will become more bright (b)They will become more dark ( c)They will disappear (d) They will be more dense
Last Answer : ( c)They will disappear
Description : n Newton's Ring experiments , the diameter of bright rings is proportional to A. Square root of Odd Natural numbers B. Natural Number C. Even Natural Number D. Square root of natural number
Last Answer : B. Natural Number
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 : In Newton's Ring experiments , the diameter of dark rings is proportional to A. Odd Natural numbers B. Natural Number C. Even Natural Number D. Square root of natural number
Last Answer : In Newton's Ring experiments , the diameter of dark rings is proportional to A. Odd Natural numbers B. Natural Number C. Even Natural Number D. Square root of natural number
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 : In Michelson ‘s interferometer 100 fringes cross the field view when the movable mirror is displaced through 0.0248 mm. Calculate the wavelength of monochromatic light used A. 5896 A 0 B.5890 A 0 C.4000 A 0 D. 4890 A 0
Last Answer : B.5890
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 : 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 : he Radius (or diameter) of bright rings in Newton's rings is (a) Directly proportional to the square root of odd numbers (b) Inversely proportional to the square root of natural numbers (c) ... to the square root of even numbers (d) Directly proportional to the square root of natural numbers
Last Answer : (a) Directly proportional to the square root of odd numbers
Description : In Newton's ring experiment, the diameter of the 15 th ring was found to be 0.590 and that of the 5 th ring was 0.336 cm. If the radius of Plano convex lens is 100 cm, compute the wavelength of light used. A. 5885 A 0 B. 5880 A o C. 5890 A o D.5850 A
Last Answer : B. 5880 A o
Description : .If we narrow the distance between two slits in Young’s experiment the fringes width __________. A. Increases B. Decreases C. Remains same D. becomes zero
Last Answer : B. Decreases
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
Last Answer : (d) Few colored bands and then general illumination
Description : Extended source is needed in A. Young's double slit experiment B. Bi prism Experiment C. Newton’s Ring Experiment D. None of them
Last Answer : C. Newton’s Ring Experiment
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 : 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
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 : 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 : 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 : The interference in thin films is because (a) The film reflects some light (b) The film is thin enough so that refracted ray is close to reflected ray (c) The reflected ray undergo path change of λ/2 (d) All of above
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 : 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 : 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 : 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 : Newton’s light illustrate the phenomenon of (a) Interference (b) Diffraction (c) Dispersion (d) Polarisation
Last Answer : (a) Interference
Description : In Newton's rings experiment, if monochromatic source of light is replaced by another monochromatic source of higher wavelength. What will be the effect on radius (or diameter)? (a) Radius (or ... be no effect (d) Radius (or diameter) will remain constant but there will be more brightness
Last Answer : (b) Radius (or diameter) will increase
Description : The phenomenon of Newton’s rings can be used to check the __________. A. Wavelength of monochromatic light B. phase coherence of two sources C. flatness of any glass surface D. velocity of light
Last Answer : A. Wavelength of monochromatic light
Description : A wedge shaped thin has (a) Non-uniform thickness (b) Zero thickness at one end and it increasing towards other end (c) Zero thickness at both ends (d) Thickness increase and decrease alternately
Last Answer : b) Zero thickness at one end and it increasing towards other end
Description : A wedge shaped thin has A. Non-uniform thickness B. Zero thickness at one end and it increasing towards other end C. Zero thickness at both ends D. Thickness increase and decrease alternately
Last Answer : B. Zero thickness at one end and it increasing towards other end
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 : In a Young's double-slit experiment the center of a bright fringe occurs wherever waves from the slits differ in the distance they travel by a multiple of: A. a fourth of a wavelength B. a half a wavelength C. a wavelength D. three-fourths of a wavelength
Last Answer : C. a wavelength
Description : Newton's rings experiment is performed and radius (or diameter) is calculated. Now Plano-convex lens is replaced with another Plano-convex lens of greater Radius of curvature. What will be effect on radius ( ... ) will increase (c) Radius (or diameter) will decrease (d) There will be no effect
Description : Newton's rings experiment is performed with air gap between lens and plate. Now that gap is filled with water. What will be effect on radius (or diameter)? (a) Radius (or diameter) will remain ... or diameter) will increase (c) Radius (or diameter) will decrease (d) There will be no effect
Last Answer : (c) Radius (or diameter) will decrease
Description : In Newton’s rings experiment, if we reduce the radius of curvature of Plano convex lens to zero, what will be effect on Newton’s rings? A. They will become brighter B. They will become darker C. They will disappear D. They will be more dense
Last Answer : C. They will disappear
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 : 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 : 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 : 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 : 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 thin film having thickness t
Last Answer : (c) Black
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 : 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 : 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 : What is true for intensity of scattered light according to Rayleigh's law? A. The intensity for scattering for light of largest wavelength more B. The light of smallest wavelength will be scattered ... C. All the wavelengths are scattered equally D. Intensity of light is not affected by scattering
Last Answer : B. The light of smallest wavelength will be scattered more