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 film
(b) Change in optical path difference at different points of film
(c) Thickness of film is different at different points of film
(d) All of above

1 Answer

Answer :

(d) All of above

Related questions

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 : 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 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 : 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 : 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

Last Answer : (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 : 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 : 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 : 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 : 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 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 : 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 : 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 : 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 : 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 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 : 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 : 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 : 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 : 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 reflected light the central fringes of Newton's ring is A. dark B. Bright C. Uniform D. Non uniform

Last Answer : A. dark

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 : Radio telescopes are better than optical telescopes because A. they can detect faint galaxies which no optical telescope can B. they can work even in cloudy conditions C. they can work during the day and night D. All of the above

Last Answer : D. All of the 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 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 : 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 : Colors in thin films are because of A. Dispersion C. Interference B. Compton effect D. Diffraction

Last Answer : C. Interference

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 : For all transparent material substances, the index of refraction A. A.is less than 1 B. B.is greater than 1 C. C.is equal to 1 D. Could be any of the given answers; it all depends on optical density

Last Answer : B. B.is greater than 1

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

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 : 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 : 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 colliodal solution is kept in dark and is illuminated by a beam of light then brightness appears at the right angle of direction of light. This effe

Last Answer : A colliodal solution is kept in dark and is illuminated by a beam of light then brightness appears at ... C. Hardy schalze effect D. None of these

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 : A thin P-type silicon sample is uniformly illuminated with light which generates excess carriers. The recombination rate is directly proportional to (A) the minority carrier mobility (B ... lifetime (C) the majority carrier concentration (D) the excess minority carrier concentration

Last Answer : A thin P-type silicon sample is uniformly illuminated with light which generates excess carriers. The recombination rate is directly proportional to the excess minority carrier concentration

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 : 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 : A soap bubble shows colours when illuminated with white light. This is due to – (1) Diffraction (2) Polarization (3) Interference (4) Reflection

Last Answer : (3) Interference Explanation: The iridescent colours of soap bubbles are caused by interfering of (internally and externally) reflected light waves and are determined by the thickness of the film. This phenomenon ... are the same as the phenomenon causing the colours in an oil slick on a wet road.

Description : A soap bubble shows colours when illuminated with white light. This is due to (1) Diffraction (2) Polarisation (3) Interference (4) Reflection

Last Answer : Interference

Description : Rainbow is due to A. absorption of sunlight in minute water droplets B. diffusion of sunlight through water droplets C. ionization of water deposits D. refraction and reflection of sunlight by water droplets

Last Answer : D. refraction and reflection of sunlight by water droplets

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.