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प्रश्न
Select the correct option:
Which mirror is used in periscope?
पर्याय
concave mirror
convex mirror
Plane mirror
parabolic mirror
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उत्तर
Plane mirror
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संबंधित प्रश्न
Give one use each of a concave and a convex mirror.
The shiny outer surface of a hollow sphere of aluminium of radius 50 cm is to be used as a mirror:
Which type of spherical mirror will it provide?
What is a spherical mirror?
State the kind of mirror used
(a) by a dentist, and
(b) as a street light reflector.
An optical device has been given to a student and he determines its focal length by focusing the image of the sun on a screen placed 24 cm from the device on the same side as the sun. Select the correct statement about the device.
(A) Convex mirror of focal length 12 cm
(B) Convex lens of focal length 24 cm
(C) Concave mirror of focal length 24 cm
(D) Convex lens of focal length 12 cm
AB and CD, two spherical mirrors, from parts of a hollow spherical ball with its centre at O as shown in the diagram. If arc AB = `1/2` arc CD, what is the ratio of their focal lengths? State which of the two mirrors will always form virtual image of an object placed in front of it and why.
A student obtained a sharp image of a burning candle, placed at the farther end of a laboratory table, on a screen using a concave mirror. For getting better value of focal length of the mirror, the subject teacher suggested him for focusing a well illuminated distant object. What should the student do?
(A) He should move the mirror away from the screen.
(B) He should move the mirror slightly towards the screen.
(C) He should move the mirror as well as the screen towards the newly selected object.
(D) He should move only the screen towards the newly selected object.
State the kind of mirror used
(a) By a dentist,
(b) As a search-light reflector.
A student traces the path of a ray of light passing through a rectangular slab.
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For measuring the angle of incidence, he must position the protractor in the manner shown in the figure:
Size of image of an object by a mirror having a focal length of 20 cm is observed to be reduced to 1/3rd of its size. At what distance the object has been placed from the mirror? What is the nature of the image and the mirror?
