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प्रश्न
a) Give two reasons to explain why reflecting telescopes are preferred over refracting type.
उत्तर
(a) The reflecting telescopes are preferred over refracting type because of the following reasons:
(i) There is no chromatic aberration in case of reflecting telescopes as the objective is a mirror.
(ii) Spherical aberration is reduced in case of reflecting telescopes by using mirror objective in the form of a paraboloid.
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संबंधित प्रश्न
Use the mirror equation to deduce that the virtual image produced by a convex mirror is always diminished in size and is located between the focus and the pole.
Use the mirror equation to deduce that an object placed between the pole and focus of a concave mirror produces a virtual and enlarged image.
Using mirror formula, explain why does a convex mirror always produce a virtual image.
The rays of different colours fail to converge at a point after going through a converging lens. This defect is called
Mark the correct options.
Which of the following (referred to a spherical mirror) do (does) not depend on whether the rays are paraxial or not?
(a) Pole
(b) Focus
(c) Radius of curvature
(d) Principal axis
A cylindrical vessel of diameter 12 cm contains 800π cm3 of water. A cylindrical glass piece of diameter 8.0 cm and height 8.0 cm is placed in the vessel. If the bottom of the vessel under the glass piece is seen by the paraxial rays (see figure), locate its image. The index of refraction of glass is 1.50 and that of water is 1.33.
A small object is placed at the centre of the bottom of a cylindrical vessel of radius 3 cm and height 4 cm filled completely with water. Consider the ray leaving the vessel through a corner. Suppose this ray and the ray along the axis of the vessel are used to trace the image. Find the apparent depth of the image and the ratio of real depth to the apparent depth under the assumptions taken. Refractive index of water = 1.33.
A light ray, going through a prism with the angle of prism 60°, is found to deviate by 30°. What limit on the refractive index can be put from these data?
Car B overtakes car A at a relative speed of 40 ms-1. How fast will the image of car B appear to move in the mirror of focal length 10 cm fitted in car A, when car B is 1.9 m away from car A?
