physics

A plane drawn perpendicular to the principal axis and passing through the principal focus.

It is a point on the principal axis at which the rays parallel to the reflection or seem to come from.

The straight-line passing through the pole and the centre of curvature of the mirror is called the principal axis.

The radius of the sphere of which a mirror is a part is called the radius of curvature.

The centre of the sphere of which the mirror is a part is called the centre of curvature.

The central point of a mirror is called its Pole.

A concave mirror or converging mirror has a reflecting surface that bulges inward.

A convex mirror, fish eye mirror, or diverging mirror is a curved mirror in which the reflective surface bulges towards the light source.

When a ray of light travels from an optically rarer to an optically denser medium it bends towards the normal.

When a ray of light travels from an optically rarer medium it bends away from the normal.