One Line Answer
Define 1 dioptre of power of a lens.
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.
1 dioptre is the power of a lens whose focal length is 1 metre.
Concept: Power of a Lens
Is there an error in this question or solution?