Lens Formula, Magnification and Power of Lens
Lens formula and magnification
Lens formula: 1/v = 1/u = 1/f, gives the relationship between the object-distance (u), image-distance (v), and the focal length (f) of a spherical lens.
Uses of spherical lens
Applications such as visual aids: spectacles, binoculars, magnifying lens, telescopes.
Power of a Lens
Power of a lens is the reciprocal of its focal length i.e 1/f (in metre). The SI unit of power of a lens is dioptre (D).
Teenager Helper 