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 : 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 : 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 : .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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : A slit of width ‘a’ is illuminated by white light. For what value of ‘a’ will the first minimum for red light fall at an angle of 300 wavelength of red light is 6500 A0 A. 1.1 x 10 -3 cm B. 1.4 X 10 -4 cm C. 1.3 X 10 -4 cm D. 1.6 X 10 -4 cm
Last Answer : C. 1.3 X 10 -4 cm
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 : 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 : 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 : 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 : 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 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 : 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 : 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 : 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 : How did you react to the laser double-slit experiment?
Last Answer : answer:I think anything is possible, and a whole lot that’s not even probable as well. We are such a puny little species of vastly limited intelligence. lol
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 : 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 : 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 : 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 : 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 : 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 : What is Young’s modulus? Describe an experiment to find out Young’s modulus of material
Last Answer : What is Young’s modulus? Describe an experiment to find out Young’s modulus of material in the form of a long straight wire.
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 : 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 : 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 : 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 : 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 : 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 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 thin film having thickness t
Last Answer : (c) Black