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प्रश्न
When a spherical mirror is held towards the sun and its sharp image is formed on a piece of a carbon paper for some time, a hole is burnt in the carbon paper.
At which point of the spherical mirror the carbon paper is placed?
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उत्तर
The carbon paper was kept at the focus of the spherical mirror.
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संबंधित प्रश्न
We can obtain an enlarged and erect image by a convex mirror.
Define Radius of curvature of the spherical mirror
Name the spherical mirror which has:
(a) virtual principal focus.
(b) real principal focus.
A small object is placed 150 mm away from a diverging lens of focal length 100 mm.
(i) Copy the figure below and draw rays to show how an image is formed by the lens.
Figure
(ii) Calculate the distance of the image from the lens by using the lens formula.
What is a spherical mirror?
What do you understand by the focus and focal length of a spherical mirror? Show them on the separate diagrams for each of a concave mirror and a convex mirror.
How is a spherical mirror used to converge a beam of light at a point? Name the type of mirror used.
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 on a screen the sharp image of a candle flame placed at the farther end of laboratory table using a concave mirror. For getting better value of focal length of the mirror, the teacher suggested to him to focus the sun. What should the student do?
(A) Should move the mirror away from the screen.
(B) Should move the mirror towards the screen.
(C) Should move the mirror and screen both towards the sun.
(D) Should move only the screen towards the sun.
Explain the meaning of the terms focus and focal length in case of a convex mirror, with the help of suitable ray diagram.
Does the mirror mentioned in part (b) form real image for all locations of the object?
For an incident ray directed towards centre of curvature of a spherical mirror the reflected ray:
Define the following term in relation to concave mirror.
Aperture
Geometric centre of the spherical mirror is ______.
An object is placed at a distance of 0.25 m
in front of a plane mirror. The distance between the object and image will be ______.
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?
A converging lens of focal length f is placed at a distance 0.3 m from an object to produce an image on a screen 0.9 m from the lens. With the object and the screen in the same positions, an image of the object could also be produced on the screen by placing a converging lens of focal length.
