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प्रश्न
A diverging lens is used in ______.
पर्याय
a magnifying glass
a car to see objects on rear side
spectacles for the correction of short sight
a simple camera
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उत्तर
A diverging lens is used in spectacles for the correction of short sight.
संबंधित प्रश्न
A 4 cm tall object is placed on the principal axis of a convex lens. The distance of the object from the optical centre of the lens is 12 cm and its sharp image is formed at a distance of 24 cm from it on a screen on the other side of the lens. If the object is now moved a little away from the lens, in which way (towards the lens or away from the lens) will he have to move the screen to get a sharp image of the object on it again? How will the magnification of the image be affected?
Explain the following term related to spherical lenses:- principal focus
Name the spherical mirror which has:
(a) virtual principal focus.
(b) real principal focus.
Name the two types of spherical mirrors. What type of mirror is represented by the:
- back side of a shining steel spoon?
- front side of a shining steel spoon?
When a spherical mirror is held towards the sun and its sharp image is formed on a piece of carbon paper for some time, a hole is burnt in the carbon paper.
- What is the nature of spherical mirror?
- Why is a hole burnt in the carbon paper?
- At which point of the spherical mirror the carbon paper is placed?
- What name is given to the distance between spherical mirror and carbon paper?
- What is the advantage of using a carbon paper rather than a white paper?
A lens forms a real image 3 cm high of an object 1 cm high. If the separation of object and image is 15 cm, find the focal length of the lens.
Explain the meaning of the terms focus and focal length in case of a convex mirror, with the help of suitable ray diagram.
State whether the image in part (a) is real or virtual?
The erect image formed by a concave mirror is of size double the size of object. How are u and v related?
Select the correct option:
Which mirror is used in periscope?
Define the following term:
concave mirror
Define the following term in relation to concave mirror.
Focal length
Does the mirror name by your form a real image for all locations? Give a reason for your answer.
AB is the object, A'B' is the image, and MM' is the position of the mirror. Complete the ray diagram showing the formation of the image and find the focal length of the mirror.
Define the term Pole.
The following Figure shows a concave mirror MM' on which a ray of light incident from a point P gets reflected to meet the principle axis at O.
(a) Find, by construction, the position of the centre of curvature of the concave mirror.
(b) Write down the value for the radius of curvature of the mirror.
(c) Calculate the focal length of the mirror.
(d ) Which relation is used in deducing the focal length from the radius of curvature?
Name the type of mirror used in the following situation:
Solar furnace
Support your answer with reason.
What is “aperture”?
