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प्रश्न
Define focal length.
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उत्तर
The distance between the pole and the principal focus is called the focal length (f) of a spherical mirror.
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संबंधित प्रश्न
Write the mirror formula. Give the meaning of each symbol which occurs in it.
A concave lens produces an image 20 cm from the lens of an object placed 30 cm from the lens. The focal length of the lens is:
(a) 50 cm
(b) 40 cm
(c) 60 cm
(d) 30 cm
Which are the two convenient rays that are chosen to construct the image by a spherical mirror for a given object? Explain with the help of suitable ray diagrams.
Draw suitable diagrams to illustrate the action of (i) concave mirror and (ii) convex mirror on a beam of light incident parallel to the principal axis.
What is meant by magnification? Write its expression. What is its sign for the (a) real (b) virtual, image?
When an object of height 1 cm is kept at a distance 4 cm from a concave mirror, its erect image of height 1.5 cm is formed at a distance 6 cm behind the mirror. Find the focal length of mirror, by drawing.
Define the following term in relation to concave mirror.
Center of curvature
Define the term principal focus in case of convex mirror. Draw a convex mirror and show its principal focus and focal length clearly.
AB is the object, A'B' is the image, and MM' is the position of the mirror. Complete the ray diagram showing the formation of the image and find the focal length of the mirror.
For a spherical mirror, ______ is true.
