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प्रश्न
An object is placed at a distance of 15 cm from a convex lens of focal length 20 cm. List four characteristics (nature, position, etc.) of the image formed by the lens.
उत्तर
Here, object distance, u = -15 cm
and focal length, f = 20 cm
Using lens formula,
`1/f = 1/v − 1/u`
`1/20 = 1/v − 1/(−15)`
`1/v = 1/20 − 1/15`
`v = − 60 cm`
Four characteristics of the image formed by the lens are :
(i) Image formed is virtual
(ii) Image is erect
(iii) Image is formed on the same side of the lens as the object
(iv) Enlarged image
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संबंधित प्रश्न
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(b) Draw the approximate path of the ray of light through the glass block and out of the other side.
Explain with the help of a diagram, why the convex lens is also called a converging lens.
Find the nature, position and magnification of the images formed by a convex lens of focal length 0.20 m if the object is placed at a distance of:
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What kind of lens can form:
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(C) inverted and enlarged
(D) inverted and highly diminished
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The focal length of a lens is positive. In this case, state the kind of lens.
Write the three characteristics of the image formed by a convex lens of focal length 20 cm for the object at distance (i) 10 cm, (ii) 30 cm, (iii) 40 cm, (iv) 60 cm from the lens.
Diagram shows an object AB placed on the principal axis B of a convex lens placed in air. F1 and F2 are the two foci of the lens.
(i) Copy the diagram:
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