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 : An index of refraction less than one for a medium would imply A. That the speed of light in the medium is the same as the speed of light in vacuum B. That the speed of light in the ... greater than the speed of light in vacuum C. Refraction is not possible D. Reflection is not possible
Last Answer : B. That the speed of light in the medium is greater than the speed of light in vacuum
Description : What is the speed of light in glycerin (n = 1.47) expressed in terms of the speed of light in a vacuum? A. 2.04c B. 1.47c C. 0.680c D. 1.00c
Last Answer : C. 0.680c
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 : 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 : 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 : 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 : 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 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 : Which of the following does NOT travel in a vacuum? A. Radio waves B. Gamma rays C. Magnetic waves D. Sound waves
Last Answer : D. Sound waves
Description : What should be the relation between refractive indices for antireflection coating made over a glass surface? A. Bair > Bfilm > Bglass B. Bair < Bfilm < Bglass C. Bair > Bfilm < Bglass D. Bair < Bfilm > Bglass
Last Answer : B. Bair < Bfilm < Bglass
Description : Second glass plate in Michelson ‘s Interferometer is known as A. Extra glass plate C. Simple Glass Plate B. Compensating glass plate D. None of these
Last Answer : B. Compensating glass plate
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 : 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 : 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 : Sound travels fastest in (a) Air (b) Water (c) Vacuum (d) Steel
Last Answer : Ans:(d)
Description : Among the following materials sound travels fastest in – (1) Steel (2) Air (3) Vacuum (4) Water
Last Answer : (1) Steel Explanation: The speed of sound is the distance travelled during a unit of time by a sound wave propagating through an elastic medium. In dry air at 20 °C (68 °F), the speed ... varies from substance to substance. Sound travels faster in liquids and non-porous solids than it does in air.
Description : Among the following materials sound travels fastest in (1) Steel (2) Air (3) Vacuum (4) Water
Last Answer : Steel
Description : When light passes from air into water, the frequency of the light remains the same. What happens to the speed? And the wavelength of light as it crosses the boundary in going from air into ... same Decreases C. Remains the same remains the same D. Decreases Increases E. Decreases Decreases
Last Answer : E. Decreases Decreases
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 : Light enters air from water. The angle of refraction will be A. Greater than the angle of incidence. B. Equal to the angle of incidence. C. Less than the angle of incidence. D. None of these
Last Answer : C. Less than the angle of incidence.
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 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 : 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 : 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 : 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 : A thin film having thickness t
Last Answer : (c) Black
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 : 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
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
Description : Antireflection coating is helps in which case of the following? A. Minimizing the reflection of light from top surface B. To absorb and control the amount of light entering into the medium C. To allow maximum light to reflect from top surface D. To allow minimum light to enter into the medium
Last Answer : A. Minimizing the reflection of light from top surface
Last Answer : C. Black
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 : __________ 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 : 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 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 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 : 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 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 : 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 : .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