Question

The power of lens is -1.5 D. Its focal length is
(a) 1.5 cm (b) 5D
(c)
The distance of distinct vision for a normal
666 cm​

Answer 1

Units of Lens Power

The SI Unit of Power is the dioptre, denoted by “D”. Definition of 1 D : A dioptre (1 D) is defined as the power of a lens whose focal length is 1 m.

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