Optics: Reflection of Light

Optics

The branch of physics that studies the behavior and properties of light.

Reflection of Light

The phenomenon where light bounces back into the same medium after striking a surface.

Laws of reflection

The angle of incidence is equal to the angle of reflection.

Regular reflection

Occurs on smooth surfaces, producing a clear image.

Irregular reflection

Occurs on rough surfaces, scattering light in different directions, producing a diffused reflection.

Image formed by a plane mirror

Virtual and erect, laterally inverted, same size as the object, image distance is equal to the object distance from the mirror.

Concave mirror

A converging mirror with the reflecting surface curved inward.

Convex mirror

A diverging mirror with the reflecting surface curved outward.

Pole (P)

The center of the reflecting surface of the mirror.

Center of curvature (C)

The center of the sphere of which the mirror is a part.

Radius of curvature (R)

The distance between the pole and the center of curvature.

Principal axis

The straight line passing through the pole and the center of curvature.

Focus (F)

The point on the principal axis where parallel rays converge (concave mirror) or appear to diverge from (convex mirror) after reflection.

Focal length (f)

The distance between the pole and the focus; f = R/2.

Image formation by concave mirrors

The characteristics of the image produced by a concave mirror depend on the object's position relative to the focal point and the center of curvature.

Magnification (m)

The ratio of the height of the image (h') to the height of the object (h).

Image formation by convex mirrors

The image formed is virtual, erect, and diminished, regardless of the object's position.

Mirror formula

1/f = 1/v + 1/u, where f is the focal length, v is the image distance, and u is the object distance.

Sign convention

Distances measured in the direction of incident light are positive, those opposite are negative.