Define 1 dioptre of power of a lens. - Science

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One Line Answer

Define 1 dioptre of power of a lens.

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Solution 1

The SI unit of power of lens is dioptre which is denoted by the letter D. 1 dioptre is defined as the power of a lens of focal length 1 metre.

Solution 2

1 dioptre is the power of a lens whose focal length is 1 metre. ​

Concept: Power of a Lens
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Chapter 5: Refraction of Light - Exercise 7 [Page 261]

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Lakhmir Singh Class 10 Physics (Science)
Chapter 5 Refraction of Light
Exercise 7 | Q 4 | Page 261
NCERT Science Class 10
Chapter 10 Light – Reflection and Refraction
Intext Questions | Q 1 | Page 184

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