Question

sign convention of lens

Answer 1

According to the convention, the focal length of a convex lens is positive and that of a concave lens is negative. According to the New Cartesian sign conventions: The optical center (O) of the lens is taken as the origin. ... All distances parallel to the principal axis are measured from the optical center of the lenses.

Answer 2

heya,,,


 For converging lenses, the focal length is always positive, while diverging lenses always have negative focal lengths.

 However, these conventions are arbitrary, and physicists could just as easily have made the signs opposite.


tysm......#gozmit