Question

What do positive and negative signs of power of lens indicates?

Answer 1

it is used for calculating lens formula and mirror formula ...Converging lenses have positive optical power, while diverging lenses have negative power. When a lens is immersed in a refractive medium, its optical power and focal length change.

Answer 2

Positive sign show that the lens is convex lens.

While negative sign show that lens is concave lens