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प्रश्न
In the concave reflector of a torch, the bulb is placed:
(a) between the pole and focus of reflector
(b) at the focus of reflector
(c) between focus and centre of curvature of reflector
(d) at the centre of curvature of reflector
उत्तर
At the focus of the reflector
When a light bulb is placed at the focus of a concave mirror reflector, the diverging light rays of the bulb are collected by the reflector and then reflected, to produce a strong, parallel-sided beam of light.
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संबंधित प्रश्न
It is desired to obtain an erect image of an object, using concave mirror of focal length of 12 cm.
Where will the image of this object be, if it is placed 24 cm in front of the mirror? Draw ray diagram for this situation also justify your answer. Show the positions of pole, principal focus and the centre of curvature in the above ray diagrams
The image of a candle flame placed at a distance of 30 cm from a mirror is formed on a screen placed in front of the mirror at a distance of 60 cm from its pole. What is the nature of the mirror? Find its focal length. If the height of the flame is 2.4 cm, find the height of its image. State whether the image formed is erect or inverted
The real image formed by a concave mirror is smaller than the object if the object is:
(a) between centre of curvature and focus
(b) at a distance greater than radius of curvature
(c) at a distance equal to radius of curvature
(d) at a distance equal to focal length
Write down a formula for the magnification produced by a concave mirror.
in terms of height of object and height of image
A converging mirror forms a real image of height 4 cm of an object of height 1 cm placed 20 cm away from the mirror:
- Calculate the image distance.
- What is the focal length of the mirror?
Which of the following are concave mirrors and which convex mirrors?
Why does a beam of light when it enters glass at an angle? Why does it not bend if it inters the glass at right angles?
Which of the following can make a parallel beam of light from a bulb falls on it?
(a) concave mirror as well as concave lens
(b) convex mirror as well as concave lens
(c) concave mirror as well as convex lens
(d) concave mirror as well as convex lens
A concave mirror produces a magnification of +4. The object is placed ______.
The concave reflecting surface of a torch got rusted. What effect would this have on the beam of light from the torch?
