Question

Define the following terms in relation to concave spherical mirrors:
(i) Pole
(ii) Center of curvature
(iii) Principal Axis
(iv) Principal Focus​

Answer 1

Answer:

Pole :- pole can be defined as the point where principal axis meets the lens. centre of curvature is the geometrical centre of the sphere of which the spherical mirror is part of. principal focus is the point on principal Axis where all the rays parallel to principal axis meet after refraction.

Centre of curvature :- the centre of a circle which passes through a curve at a given point and has the same tangent and curvature at that point

Principal axis :- each of three mutually perpendicular axes in a body about which the moment of inertia is at a maximum.

Principal focus :- In geometrical optics, a focus, also called an image point, is the point where light rays originating from a point on the object converge. Although the focus is conceptually a point, physically the focus has a spatial extent, called the blur circle.