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प्रश्न
Concave mirrors are used by dentists to examine teeth. Why?
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उत्तर
As a dentist’s head mirror: You would have seen a circular mirror attached to a band tied to the forehead of the dentist/ENT specialist. A parallel beam of light is made to fall on the concave mirror; this mirror focuses the light beam on a small area of the body (such as teeth, throat etc.).
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संबंधित प्रश्न
"A concave mirror of focal length 15 cm can form a magnified, erect as well as inverted image of an object placed in front of it." Justify this statement stating the position of the object with respect to the pole of the mirror in both the cases for obtaining the images.
List four specific characteristics of the images of the objects formed by convex mirrors.
A 3 cm tall object is placed 18 cm in front of a concave mirror of focal length 12 cm. At what distance from the mirror should a screen be placed to see a sharp image of the object on the screen. Also calculate the height of the image formed.
Described with the help of a diagram, the nature, size and position of the image formed when an object is placed beyond the centre of curvature of a concave mirror.
At what distance from a concave mirror focal length 10 cm should an object 2 cm long be placed in order to get an erect image 6 cm tall?
If the radius of curvature of a concave mirror is 20 cm, its focal length is:
In the following diagram. MM' is a concave mirror and AB is an object. Draw on your answer-sheet a ray diagram to show the formation of image of this object.
Draw the ray diagram and also state the position, the relative size and the nature of image formed by a concave mirror when the object is placed at the centre of curvature of the mirror.
Answer the following question:
An object is placed at a distance of 30 cm from a concave lens of focal length 30 cm.
(i) Use the lens formula to determine the distance of the image from the lens.
(ii) List four characteristics of the image (nature, position, size, erect/inverted) in this case.
(iii) Draw a labelled diagram to justify your answer of the part (ii)
A concave mirror of focal length 20 cm forms an image having twice the size of object. For the virtual position of object, the position of object will be at ______.
