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प्रश्न
Why are concave mirrors used in solar devices?
उत्तर
A concave mirror is also known as a converging mirror because of its ability to focus parallel rays of light at a single point on its focal plane. This property is used in solar devices. Parallel rays from the Sun, when reflected by the concave mirror, are focused at a particular point, generating a significant amount of heat. This heat is essential for the proper functioning of solar devices, such as solar cookers or solar furnaces.
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संबंधित प्रश्न
To determine the approximate value of the focal length of a given concave mirror, you focus the image of a distant object formed by the mirror on a screen. The image obtained on the serene, as compared to the object is always:
(a) Laterally inverted and diminished
(b) Inverted and diminished
(c) Erect and diminished
(d) Erect and highly diminished
Draw ray diagrams to show the principal focus of a concave mirror.
Out of convex mirror and concave mirror, whose focus is situated behind the mirror?
Fill in the following blank with suitable word:
A concave mirror .......... rays of light whereas convex mirror ............ rays
What is a spherical mirror? Distinguish between a concave mirror and a convex mirror.
Define (i) principal focus of a concave mirror, and (ii) focal length of a concave mirror.
For what position of an object, a concave mirror forms a real image equal in size to the object?
With the help of a labelled ray diagram, describe how a converging mirror can be used to give an enlarged upright image of an object.
Explain why, concave mirrors are used as shaving mirrors.
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
At what distance from a concave mirror of focal length 10 cm should an object be placed so that:
its real image is formed 20 cm from the mirror?
Name the lens which can concentrate sun's rays to a point and burn a hole in a piece of paper.
With the help of a labelled diagram, explain how a concave lens diverges a beam of parallel light rays. Mark the principal axis, optical centre, principal focus and focal length of the concave lens on the diagram.
Complete the following diagrams in figure by drawing the reflected rays for the incident rays 1 and 2 if F is the focus and C is the centre of curvature.
Draw a ray diagram to show the formation of image of an object placed at the centre of curvature of a concave mirror. State the position, size and nature of the image.
Draw a ray diagram to show the formation of image of an object placed between the pole and focus of a concave mirror. State the position, size and nature of the image.
A student obtained a sharp image of the grills of a window on a screen using a concave mirror. His teacher remarked that for getting better results a well lit distant object (preferably the sun) should be focussed on the screen. What should be done for this purpose?
(A) Move the screen slightly away from the mirror
(B) Move the mirror slightly towards the screen
(C) Move the screen and the mirror away from the object
(D) Move the screen and the mirror towards the object
A student has to trace the path of a ray of light passing through a rectangular glass slab for four different values of angle of incidence.
(a) Write two important precautions for this experiment.
(b) List two conclusions the student will draw based on his experiment.
In the headlights of motor vehicles, ______ mirrors are used as reflectors.
Between which two points of a concave mirror should an object be placed to obtain a magnification of -2?
