what is meant by power of lense ?what is the unit?

Answer 1

The power of a lens is the reciprocal of its focal length. In other words, the inverse of its focal length.
The unit of power is "diopters", which is really just meters to the
-1 power (in other words, the inverse of meters).
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Answer 2

As light rays pass through a lens with power, the rays are bent or refracted. In a lens with a plus power, the light rays converge or are refracted toward one another. The point at which the light rays converge is called the focal point and in a plus lens, is behind the lens surface. In a lens with a minus power, the light rays diverge or are refracted away from one another. If these rays are extrapolated or traced back toward the light source, the lines will converge and form a focal point in front of the lens surface.



The lens power is relative to the focal distance or the distance between the focal point and the lens. More specifically, lens power is the reciprocal of the focal distance in meters. Lens power is expressed in diopters (D).



Power = 1 / Focal Distance

Answer 3

The reciprocal of focal length in meter is called power of lens. The S.I. unit of power of lens is diopter.
Mathematically,
Power of lens(p)= 1/focal length(f)
It says that power of lens is inversely proportion to focal length of respected lens. It is a ability of lens.

Answer 4

power of lense is reciprocal of focal length.its unit is dioptre

Answer 5

It is the ability of the lens to converge(convex lens) or diverge(concave lens) the ray of light. it is inverse of the focal length of the lens, i.e., 1/f.

Answer 6

forgot the definition....but its unit is Dioptres