Question

Define :

i) Focus ii) Focal length iii) Radius of curvature iv) Principal axis
​

Answer 1

Answer:

i)A focus is a point at which rays of light, heat, or other radiation meet after being refracted or reflected.

ii)The focal length of an optical system is a measure of how strongly the system converges or diverges light.

iii)The distance from the vertex to the center of curvature is known as the radius of curvature. The radius of curvature is the radius of the sphere from which the mirror was cut.

iv) Principal axis is a line passing through the center of the surface of a lens or spherical mirror and through the centers of curvature of all segments of the lens or mirror.

Hope it helps<3