[{"id":146078,"question":"At constant volume temperature is increased. Then","choices":[{"text":"Collision on walls will be less","value":"A"},{"text":"Number of collisions per unit time will increase","value":"B"},{"text":"Collisions will be in straight lines","value":"C"},{"text":"Collisions will not change","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":146077,"question":"The number of translation degrees of freedom for a diatomic gas is","choices":[{"text":"2","value":"A"},{"text":"3","value":"B"},{"text":"5","value":"C"},{"text":"6","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":146076,"question":"All of the following statements are correct except","choices":[{"text":"The total focal length of astronomical telescope is the sum of the focal lengths of its two lenses","value":"A"},{"text":"The image formed by the astronomical telescope is always erect because the effect of the combination of the two lenses is divergent","value":"B"},{"text":"The magnification of an astronomical telescope can increases by decreasing the focal length of the eyepiece","value":"C"},{"text":"The magnifying power of the refracting type of astronomical telescope is the ratio of the focal length of the objective to that of the eye piece","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":146075,"question":"The length of a telescope is 36 cm. The focal lengths of its lenses can be","choices":[{"text":"30 cm, 6 cm","value":"A"},{"text":"-30 cm, -6 cm","value":"B"},{"text":"30 cm, -6cm","value":"C"},{"text":"-30cm, 6cm","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":146074,"question":"To increase the magnification of a telescope","choices":[{"text":"The objective lens should be of large focal length and eyepiece should be of short focal length","value":"A"},{"text":"The objective and eyepiece both should be of large focal lengths","value":"B"},{"text":"Both the objective and eyepiece should be of smaller lengths","value":"C"},{"text":"The objective should be small focal length and eyepiece should be of large focal length","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":146073,"question":"If tube length of astronomical telescope is 105 cm and magnifying power is 20 for normal setting. Calculate the focal length of objective","choices":[{"text":"100 cm","value":"A"},{"text":"10 cm","value":"B"},{"text":"20 cm","value":"C"},{"text":"25 cm","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":146072,"question":"A planet is observed by an astronomical refracting telescope having an objective of focal length 16 m and an eyepiece of focal length 2 cm.","choices":[{"text":"The distance between the objective and the eyepiece is 8 m","value":"A"},{"text":"The angular magnification of the planet is 200","value":"B"},{"text":"The image of the planet is inverted","value":"C"},{"text":"The objective is smaller than the eyepiece","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":146071,"question":"A lens behaves as a converging lens in air and a diverging lens in water. The refractive index of the material is","choices":[{"text":"Equal to unity","value":"A"},{"text":"Equal to 1.33","value":"B"},{"text":"Between unity and 1.33","value":"C"},{"text":"Greater than 1.33","value":"D"},{"value":"E"}],"correctAnswer":3},{"id":146070,"question":"An object is placed at a distance of f/2 from a convex lens. The image will be","choices":[{"text":"At one of the foci, virtual and double its size","value":"A"},{"text":"At, 3f/2, real and inverted","value":"B"},{"text":"At 2f, virtual and erect","value":"C"},{"text":"At f, real and inverted","value":"D"},{"value":"E"}],"correctAnswer":1},{"id":146069,"question":"When the length of a microscope tube increases, its magnifying power","choices":[{"text":"Decreases","value":"A"},{"text":"Increases","value":"B"},{"text":"May increases or decreases depending on the observer and the place of observation","value":"C"},{"text":"Does not change","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":146068,"question":"When the length of a microscope tube increase, its magnifying power","choices":[{"text":"Decreases","value":"A"},{"text":"Increases","value":"B"},{"text":"Does not Change","value":"C"},{"text":"May increase or decrease depending on the observer and the place of observation","value":"D"},{"value":"E"}],"correctAnswer":2},{"id":146067,"question":"A converging lens is used to form an image on a screen. When the upper half of the lens is covered by an opaque screen","choices":[{"text":"Half the image will disappear","value":"A"},{"text":"No change either in size or in intensity","value":"B"},{"text":"Intensity of image will increase","value":"C"},{"text":"Intensity of the image will decrease","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":146066,"question":"A fly is sitting on the objective of a telescope pointed towards the moon.<div>What effect is expected on the photography of the moon taken through the telescope?</div>","choices":[{"text":"The entire of view blocked","value":"A"},{"text":"There is an image of the fly on the photography","value":"B"},{"text":"There is no effect at all","value":"C"},{"text":"There is a reduction in the intensity of the image","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":146065,"question":"Huygen's wave theory of light cannot explain","choices":[{"text":"Diffraction","value":"A"},{"text":"Interference","value":"B"},{"text":"Polarization","value":"C"},{"text":"Photoelectric effect","value":"D"},{"value":"E"}],"correctAnswer":4},{"id":146064,"question":"The contrast in the fringes in any interference pattern depends on","choices":[{"text":"Fringe width","value":"A"},{"text":"Intensity ratio of the sources","value":"B"},{"text":"Distance between the slits","value":"C"},{"text":"Wavelength","value":"D"},{"value":"E"}],"correctAnswer":2}]