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प्रश्न
With the help of an appropriate ray diagram, state the sign conventions for reflection by a spherical mirror.
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उत्तर
The sign convention for reflection by spherical mirrors is as follows:-
- The object is always placed to the left of the mirror.
- All distances parallel to the principal axis are measured from the pole of the mirror.
- All the distances measured to the right of the origin are taken as positive, while those measured to the left of the origin are taken as negative.
- Distances measured perpendicular to and above the principal axis are taken as positive.
- Distances measured perpendicular to and below the principal axis are taken as negative.
- The focal length of a convex mirror is positive, while that of a concave mirror is negative.
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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.
Draw a ray diagram to show the path of the refracted ray in each of the following cases:-
A ray of light incident on a concave lens is
(i) passing through its optical centre.
(ii) parallel to its principal axis.
(iii) directed towards its principal focus.
It is desired to obtain an erect image of an object, using concave mirror of focal length of 12 cm.
Where will the image of this object be, if it is placed 24 cm in front of the mirror? Draw ray diagram for this situation also justify your answer. Show the positions of pole, principal focus and the centre of curvature in the above ray diagrams
The image formed by a concave mirror is observed to be virtual, erect and larger than the object. Where should the position of the object be relative to the mirror? Draw ray diagram to justify your answer.
We wish to obtain an erect image of an object, using a concave mirror of focal length 15 cm. What should be the range of distance of the object from the mirror? What is the nature of the image? Is the image larger or smaller than the object? Draw a ray diagram to show the image formation in this case.
ill in the following blank with suitable word:
For a convex mirror, parallel rays of light appear to diverge from a point called the ......... .
Draw diagram to represent the action of a concave mirror on a beam of parallel light rays. Mark on this diagram principal axis, focus F, centre of curvature C, pole P and focal length f, of the concave mirror.
If an object is placed at the focus of a concave mirror, where is the image formed?
Explain why, a ray of light passing through the centre of curvature of a concave mirror gets reflected back along the same path.
Explain why, concave mirrors are used as shaving mirrors.
An object is placed at a distance of 10 cm from a concave mirror of focal length 20 cm.
Calculate the image distance.
An object is placed just outside the principal focus of concave mirror. Draw a ray diagram to show how the image is formed, and describe its size, position and nature.
A concave mirror cannot be used as:
(a) a magnifying mirror
(b) a torch reflector
(c) a dentist's mirror
(d) a real view mirror
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.
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.
Explain the images formed by a concave mirror.
A 10 mm long awl pin is placed vertically in front of a concave mirror. A 5 mm long image of the awl pin is formed at 30 cm in front of the mirror. The focal length of this mirror is ______.
An image formed by a lens is erect. Such an image could be formed by a
______ mirrors magnify the object placed close to them.
What is a concave and convex mirror?
