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प्रश्न
Fig shows an object PQ placed on the principle axis of a lens L. The two foci of the kens are F1 and f2. The image formed by the lens is erect, Virtual and dimnished.
(i) Draw the outline ofthe lens L used and Named it.
(ii) Draw a ray of light starting from Q and passing through O. show the same ray after refraction by the lens.
(iii) Draw another ray from Q Which is incident parallel to the principle axis and show how it emerges after refraction from the lens.
(iv) Locate the final image formed.
उत्तर
(i) Outline of lens is drawn in above diagram. It is a concave lens.
(ii) Shown in diagram above.
(iii) shown in diagram above.
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संबंधित प्रश्न
In the diagram below, XX’ represents the principal axis, O the optical centre and F the focus of the lens. Complete the path of rays A and B as they emerge out of the lens.
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| (a) | (b) |
Study the diagram shown in Fig. 5.56
where is the object located?
State the condition of the following:
A ray passes undeviated through the lens.
In the following diagram , the object and the image formed by the respective lenses are shown. Complete the ray diagram, and locate the focus. Find the focal length of the lens.
In the following diagram , the object and the image formed by the respective lenses are shown. Complete the ray diagram, and locate the focus. Find the focal length of the lens.
Fig. shows two rays of light Op and OQ coming from an object at the bottom of a pond, incident on the water surface.
(a) Mark on the diagram
(i) The angle of incidence of ray OP,
(ii) The angle of refraction of ray Op,
(iii) The position of image of the object as seen from above.
(iv) An approximate path of the ray OQ.
(b) Explain, why do the rays of light change directions on passing from water to air.
(c) A fish in water sees everything outside the water by rays of light entering its eye in a small cone of light. Draw a diagram and explain how does this happen.
A lens forms the image of an object placed at a distance of 45 cm from it on a screen placed at a distance 90 cm on the other side of it. Name the kind of lens.
How will you differentiate between a convex and a concave lens by looking at a printed page?
Complete the following diagram and state what happens to the ray of light after refraction through the lens.
Mixture of red + blue + green is passed through a convex lens as shown in the diagram below. State whether the ray passes through a single point or through different points on the principal axis after refraction.
