[{"id":126266,"question":"On a diffraction grating a large number of close parallel equidistant slits are ruled on it","choices":[{"text":"By hand","value":"A"},{"text":"electronically","value":"B"},{"text":"mechanically","value":"C"},{"text":"none of them","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":126265,"question":"Diffraction is concerned with the superposition of","choices":[{"text":"very large number of secondary wavelets","value":"A"},{"text":"a few secondary wavelets","value":"B"},{"text":"two secondary wavelets","value":"C"},{"text":"no secondary","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":126264,"question":"The diffraction is found to be prominent when the wavelength of light is","choices":[{"text":"small as compared with the size of obstacle","value":"A"},{"text":"large as compared with the size of obstacle","value":"B"},{"text":"equal as compared with the size of obstacle","value":"C"},{"text":"Very small as compared with the size of the obstacle","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":126262,"question":"The property of bending of light around obstacies is called","choices":[{"text":"interference","value":"A"},{"text":"reflection","value":"B"},{"text":"diffraction","value":"C"},{"text":"polarization","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":126261,"question":"The length of the standard metre measured by Michelsion's interferometer comes out to be","choices":[{"text":"1,553, 163.5 wavelength","value":"A"},{"text":"1553.5 wavelength","value":"B"},{"text":"155316.5 wavelength","value":"C"},{"text":"none of them","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":126259,"question":"If the wavelength of light used in Michelsion's interferometer is 400 nm and the moveable mirror only moved throughλ/4, then the length moved will be","choices":[{"text":"10 nm","value":"A"},{"text":"10-2mm","value":"B"},{"text":"1 nm","value":"C"},{"text":"10-4mm","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":126256,"question":"Wavelength of X-rays falling at a glancing angle of 30° on a crystal with atomic spacing 2 x 10-10m for first order diffraction is","choices":[{"text":"4 x 10-10m","value":"A"},{"text":"2 x 10-10m","value":"B"},{"text":"0.2 x 10-10m","value":"C"},{"text":"20 x 10-10m","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":126254,"question":"In Michelsion's interoferometer, if the moveable mirror is moved through a distance 0.05 mm and 500 finges are observed, then the wavelength of light used is","choices":[{"text":"1 x 10-7m","value":"A"},{"text":"2 x 10-7m","value":"B"},{"text":"1.5 x 10-7m","value":"C"},{"text":"1 x 10-8m","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":126252,"question":"In Michelsion's interferometer, if 'm' number of fringes are passed in front of a reference point when the moveable mirror is moved a distance L, then","choices":[{"text":"L = mλ","value":"A"},{"text":"L = 2mλ","value":"B"},{"text":"L = mλ/2","value":"C"},{"text":"L = 3/2 mλ","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":126251,"question":"In Michelsion's interferometer, if a dark fringe is seen in the beginning, the next dark fringe will appear by moving the moveable mirror through a distance","choices":[{"text":"λ/2","value":"A"},{"text":"λ/4","value":"B"},{"text":"λ","value":"C"},{"text":"2λ","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":126250,"question":"Successive dark and bright fringes are formed each time the moveable mirror in Michelsion's interferometer is moved a distance","choices":[{"text":"λ/2","value":"A"},{"text":"λ/4","value":"B"},{"text":"λ","value":"C"},{"text":"3/2λ","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":126248,"question":"If the moveable mirror in Michelsion's interferometer moves a distanceλ/2, the path difference changes by","choices":[{"text":"λ/4","value":"A"},{"text":"λ/2","value":"B"},{"text":"λ","value":"C"},{"text":"3/2λ","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":126245,"question":"In Michelsion's interferometer the path difference is varied by moving","choices":[{"text":"compensatory plate","value":"A"},{"text":"moveable mirror","value":"B"},{"text":"fixed mirror","value":"C"},{"text":"telescope","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":126244,"question":"Michelesion's interferometer is an instrument usually used to measure","choices":[{"text":"intensity of light","value":"A"},{"text":"speed of light","value":"B"},{"text":"wavelength of light","value":"C"},{"text":"dispersion of light","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":126243,"question":"The idea of Michelsion's interferometer is based on the","choices":[{"text":"reflection of light","value":"A"},{"text":"interference of light","value":"B"},{"text":"refraction of light","value":"C"},{"text":"all of them","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":126242,"question":"Michelsion devised the Michelson's interferometer in","choices":[{"text":"1981","value":"A"},{"text":"1891","value":"B"},{"text":"1851","value":"C"},{"text":"1881","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":126241,"question":"Michelson's interferometer is an instrument that is capable of measuring distance with","choices":[{"text":"low precision","value":"A"},{"text":"high precision","value":"B"},{"text":"extremely high precision","value":"C"},{"text":"extremely low precision","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":126240,"question":"At the point of contact of the lens and the glass plate, the incident and reflected rays interfere","choices":[{"text":"constructively","value":"A"},{"text":"destructively","value":"B"},{"text":"either of them","value":"C"},{"text":"none of them","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":126239,"question":"Newton's rings are formed as a result of","choices":[{"text":"diffraction of light","value":"A"},{"text":"dispersion of light","value":"B"},{"text":"interference of light","value":"C"},{"text":"polarization of light","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":126238,"question":"At the point of contact of the lens and the glass plate, the Newton's ring is","choices":[{"text":"dark","value":"A"},{"text":"bright","value":"B"},{"text":"either of them","value":"C"},{"text":"neither of them","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":126237,"question":"In the Newton's ring, as we proceed towards the periphery of the lens, the thickness of air film","choices":[{"text":"gradually decreases","value":"A"},{"text":"gradually increases","value":"B"},{"text":"suddenly becomes zero","value":"C"},{"text":"all of them","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":126231,"question":"In Newton's rings the thickness of air film at the point of contact is","choices":[{"text":"maximum","value":"A"},{"text":"minimum","value":"B"},{"text":"equal to wavelength","value":"C"},{"text":"zero","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":126230,"question":"In the thin film, the path difference between the two reflecting waves depends upon","choices":[{"text":"thickness of film","value":"A"},{"text":"nature of film","value":"B"},{"text":"angle of incidence","value":"C"},{"text":"all of them","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":126227,"question":"When monochromatic light is incident, making certain angle, on a thin parallel film, the interference fringes formed are","choices":[{"text":"straight","value":"A"},{"text":"circular","value":"B"},{"text":"square","value":"C"},{"text":"plane","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":126225,"question":"When sunlight falls on a soap bubble (film), it appears coloured because of","choices":[{"text":"interference of light","value":"A"},{"text":"dispersion of light","value":"B"},{"text":"polarization of light","value":"C"},{"text":"diffraction of light","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":126223,"question":"A thin film is a transparent medium whose thickness is comparable with the wavelength of","choices":[{"text":"light","value":"A"},{"text":"sound","value":"B"},{"text":"any one of them","value":"C"},{"text":"none of them","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":126222,"question":"The bright fringes are termed as","choices":[{"text":"minimum","value":"A"},{"text":"maximum","value":"B"},{"text":"bright spots","value":"C"},{"text":"dark spots","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":126220,"question":"Layer of oil on water in sunlight appears coloured due to","choices":[{"text":"diffraction of light","value":"A"},{"text":"dispersion","value":"B"},{"text":"interference of light","value":"C"},{"text":"polarization of light","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":126218,"question":"In Young's double slit experiment, the widths of dark and bright fringes are","choices":[{"text":"different","value":"A"},{"text":"equal","value":"B"},{"text":"zero","value":"C"},{"text":"variable","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":126216,"question":"The interference fringes are of","choices":[{"text":"equal width","value":"A"},{"text":"variable width","value":"B"},{"text":"zero width","value":"C"},{"text":"non-uniform width","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":126214,"question":"In Young's double slit experiment, the fringe width depends on","choices":[{"text":"wavelength of the light used","value":"A"},{"text":"distance between the slits and screen","value":"B"},{"text":"distance between the slits","value":"C"},{"text":"all of them","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":126212,"question":"The fringes produced in Young's double slit experiment will be wider if the distance between the two slits is","choices":[{"text":"small","value":"A"},{"text":"large","value":"B"},{"text":"zero","value":"C"},{"text":"very large","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":126210,"question":"In Young's double slit experiment fringe width (or fringe spacing) depends","choices":[{"text":"inversely on wavelength","value":"A"},{"text":"directly on wavelength","value":"B"},{"text":"directly on square of wavelength","value":"C"},{"text":"inversely on square of wavelength","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":126207,"question":"The distance between the centres of two consecutive bright fringes (or dark fringes) is called","choices":[{"text":"wavelength","value":"A"},{"text":"fringe width","value":"B"},{"text":"amplitude","value":"C"},{"text":"path difference","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":126206,"question":"When one mirror of Michelson interferometer is moved a distance of 0.5 mm. 2000 fringes are observed, the wavelength of light used is","choices":[{"text":"5000 nm","value":"A"},{"text":"5000 A°","value":"B"},{"text":"500 cm","value":"C"},{"text":"2000 A°","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":126205,"question":"When crest of one wave coincides with the trough of the other wave, it give rise to","choices":[{"text":"dispersion","value":"A"},{"text":"constructive interference","value":"B"},{"text":"destructive interference","value":"C"},{"text":"polarization","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":126203,"question":"At points where the crest (or trough) of one wave coincides with the crest (or trough) of the other wave, the wave produces","choices":[{"text":"destructive interference","value":"A"},{"text":"constructive interference","value":"B"},{"text":"diffraction","value":"C"},{"text":"dispersion","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":126202,"question":"Which phenomenon of light takes place in Young's double-slit experiment?","choices":[{"text":"polarization of light","value":"A"},{"text":"diffraction of light","value":"B"},{"text":"interference of light","value":"C"},{"text":"reflection of light","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":126201,"question":"Which of the following theories of light are explained by the Young's double slit experiment?","choices":[{"text":"wave theory of light","value":"A"},{"text":"particle nature of light","value":"B"},{"text":"dual nature of light","value":"C"},{"text":"corpuscular nature of light","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":126200,"question":"Two light sources obtained from single source are called","choices":[{"text":"non-coherent sources","value":"A"},{"text":"coherent sources","value":"B"},{"text":"monochromatic sources","value":"C"},{"text":"spherical sources","value":"D"},{"value":"E"}],"correctAnswer":2}]