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प्रश्न
An object of 10 cm is placed in front of a plane mirror. The height of image will be …………….
(a) 5 cm
(b) 15 cm
(c) 20 cm
(d) 10 cm
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उत्तर
(d) 10 cm
The image formed by a plane mirror is always of the same size as that of the object.
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संबंधित प्रश्न
The height of the image formed by an object of height 10 cm placed in front of a plane mirror is __________.
(a) 5 cm
(b) 10 cm
(c) 15 cm
(d) 20 cm
The image formed by a concave mirror is virtual, erect and magnified. The position of object is:
(a) at focus
(b) between focus and centre of curvature
(c) at pole
(d) between pole and focus
When an object is placed 20 cm from a concave mirror, a real image magnified three times is formed. Find:
(a) the focal length of the mirror.
(b) Where must the object be placed to give a virtual images three times the height of the object?
A dentist's mirror has a radius of curvature of 3 cm. How far must it be placed from a small dental cavity to give a virtual image of the cavity that is magnified five times?
A virtual, erect and magnified image of an object is to be obtained with a convex lens. For this purpose,the object should be placed:
(a) between 2F and infinity
(b) between F and optical centre
(c) between F and 2F
(d) at F
Write down the magnification formula for a lens in terms of object distance and image distance. How does this magnification formula for a lens differ from the corresponding formula for a mirror?
An erect image 2.0 cm high is formed 12 cm from a lens, the object being 0.5 cm high. Find the focal length of the lens.
An object placed 4 cm in front of a converging lens produces a real image 12 cm from the lens.
(a) What is the magnification of the image?
(b) What is the focal length of the lens?
(c) Draw a ray diagram to show the formation of image. Mark clearly F and 2F in the diagram.
An object is 0.09 m from a magnifying lens and the image is formed 36 cm from the lens. The magnification produced is:
(a) 0.4
(b) 1.4
(c) 4.0
(d) 4.5
A magnifying lens has a focal length of 100 mm. An object whose size is 16 mm is placed at some distance from the lens so that an image is formed at a distance of 25 cm in front of the lens.
Where should the object be placed if the image is to form at infinity?
An image formed on a screen is three times the size of the object. The object and screen are 80 cm apart when the image is sharply focussed.
Calculate focal length of the lens.
A convex mirror has a focal length of 18 cm. The image of an object kept in front of the mirror is half the height of the object. What is the distance of the object from the mirror?
An object of height 7 cm is kept at a distance of 25 cm in front of a concave mirror. The focal length of the mirror is 15 cm. At what distance from the mirror should a screen be kept so as to get a clear image? What will be the size and nature of the image?
Assertion: The focal length of the mirror is /and the distance of the object from the focus is V then the magnification of the mirror will be `("f"/"f−u")`
Reason: Magnification = `"image distance"/ "object distance"` = `(-"v"/"u")`
What do you mean by linear magnification?
What is the nature of the image formed by a concave mirror if the magnification produced by the mirror is +4?
The power of a lens is +4D. Find the focal length of this lens. An object is placed at a distance of 50 cm from the optical centre of this lens. State the nature and magnification of the image formed by the lens and also draw a ray diagram to justify your answer.
