मराठी

Define the power of a lens.

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प्रश्न

Define the power of a lens.

Define the term power of a lens.

व्याख्या
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उत्तर १

Power of a lens is defined as the ability of a lens to bend the rays of light. It is given by the reciprocal of focal length in metre.

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उत्तर २

The power of a lens is a measure of the deviation produced by it in the path of rays refracted through it.

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  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 5: Refraction through a Lens - EXERCISE - 5 (C) [पृष्ठ १२६]

संबंधित प्रश्‍न

Calculate the focal length of a corrective lens having power +2D.


What is meant by a power of a lens? Define its SI unit. 


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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.


Express the power (with sign) of a concave lens of focal length 20 cm.


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A convex lens is of focal length 20 cm. Find its power.


If the lens is of focal length 25 cm. Calculate the power of the lens.


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Assertion and reasoning type

  1. Assertion: Myopia is due to the increase in the converging power of eye lens.
  2. Reason: Myopia can be corrected with the help of concave lens.

The above lens has a focal length of 10 cm. The object of height 2 mm is placed at a distance of 5 cm from the pole. Find the height of the image.


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