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प्रश्न
You are provided with a printed piece of paper. Using this paper how will you differentiate between a convex lens and a concave lens?
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उत्तर
First, we place the lens on a piece of printed paper. Then we lift it slowly. If the words of the printed paper, seen through the lens becomes bigger than is convex lens otherwise concave lens.
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संबंधित प्रश्न
On the basis of the experiment, "To trace the path of a ray of light through a rectangular glass slab", students of a class arrived at which one of the following conclusions?
(A) Angle of incidence is greater than the angle of emergence.
(B) Angle of emergence is smaller than the angle of refraction.
(C) Emergent ray is parallel to the refracted ray.
(D) Incident ray and emergent ray are parallel to each other.
How is the reflection of light ray from a plane mirror different from the refraction of light ray as it enters a block of glass?
Fill in the blanks to complete the following sentence
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a) The blasts in the stars.
b) Absorption of star light by the atmosphere.
c) Motion of the stars.
d) Changing refractive index of gases in the atmosphere.
Rewrite the following statement by selecting the correct option:
If a ray of light strikes a glass slab at an angle of 600 with the surface of the slab, the angle of incidence must be __________________.
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Draw ray of light bending towards the normal while passing from glass to water. Label your diagrams.
A ray of light PQ is incident normally on the hypotenuse of a right-angled prism ABC as shown in the diagram given below:
(i) Copy the diagram and complete the path of the ray PQ till it emerges from the prism.
(ii) What is the value of the angle of deviation of the ray?
(iii) Name an instrument where this action of the prism is used.
