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प्रश्न
Name the physical quantity whose unit is dioptre.
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उत्तर
The power of a lens is a physical quantity with dioptre as it's unit.
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संबंधित प्रश्न
State power of a lens S.I. unit.
A convex lens forms a real and inverted image of a needle at a distance of 50 cm from it. Where is the needle placed in front of the convex lens if the image is equal to the size of the object? Also, find the power of the lens.
Consider two statements A and B given below:
A: real image is always inverted
B: virtual image is always erect
Out of these two statements:
The lens A has a focal length of 25 cm whereas another lens B has a focal length of 60 cm. Giving reason state, which lens has more power: A or B.
What is the power of a convex lens lens whose focal length is 80 cm?
What is the nature of a lens whose power is, −4 D?
The focal length of a lens is +150 mm. What kind of lens is it and what is its power?
An object of height 4.25 mm is placed at a distance of 10 cm from a convex lens of power +5D. Find (i) the focal length of the lens, and (ii) the size of the image.
The power of a lens is +2.0D. Its focal length should be :
State the condition for the following a ray passes undeviated through the lens .
The power of a lens is + 1.0 D is :
A convex lens produces a double size real image when an object is placed at a distance of 18 cm from it. Where should the object be placed to produce a triple size real image?
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.
A stick partly immersed in water appears to be bent. Draw a ray diagram to show the bending of the stick when placed in water and viewed obliquely from above.
If the lens is of focal length 25 cm. Calculate the power of the lens.
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The focal length of a concave lens is 20 cm. The focal length of a convex lens is 25 cm. These two are placed in contact with each other. What is the power of the combination? Is it diverging, converging or undeviating in nature?
The same size images are formed by a convex lens when the object is placed at 20 cm or at 10 cm from the lens. The focal length of convex lens is ______ cm.
The focal length of a double convex lens is equal to the radius of curvature of either surface. What is the refractive index of its material?
