Advertisements
Advertisements
प्रश्न
In what unit is the power of a lens expressed?
Advertisements
उत्तर
Its unit is Dioptre (D).
APPEARS IN
संबंधित प्रश्न
Ranbir claims to have obtained an image twice the size of the object with a concave lens. Is he correct? Give a reason for your answer.
How is the power of a lens related to its focal length?
What is the nature of a lens whose power is, −4 D?
On reducing the focal length of a lens, its power ______.
Mohan obtained a sharp inverted image of a distant tree on the screen placed behind the lens. He then moved the screen and tried to look through the lens in the direction of the object. He would see:
(1) a blurred image on the wall of the laboratory.
(2) an erect image of the tree on the lens.
(3) no image as the screen has been removed
(4) an inverted image of the tree at the focus of the lens.
A 5.0 diopter lens forms a virtual image which is 4 times the object placed perpendicularly on the principal axis of the lens. Find the distance of the object from the lens.
If focal length of a convex lens is 20 cm at what is the power of the lens?
Increase in the converging power of eye lens cause ‘hypermetropia'
A point object is placed at O in front of a glass sphere as shown in figure.

Show the formation of the image by the sphere.
The lens of power + 1·0 D is ______.
