reflection of light

reflection

light travelling in a medium encounters a boundary leading to a second medium. part of the incident light ray returns back to the first medium. this is reflection

mirrors

can be plane or curved
mirrors redirect light rays and form an image of objects
- mirrors are made on a thin layer of aluminium on a polished surface

what are the two types of reflection

1. Specular (regular) Reflection
2. Diffuse Reflection

specular (regular) reflection

when a parallel pencil of rays is incident on a highly reflected surface, the light rays are reflected in a single direction

diffuse reflection

when a parallel pencil of rays is incident on a irregular or rough surface, the light rays are reflected in all directions (e.g. paper)

laws of reflection

1) incident angle is equal to the angle of reflection
2) incident ray, reflected ray and normal ray are all in the and plane, which is perpendicular to the surface

plane mirror distance

for a plane mirror the image distance behind the mirror is the same as the object distance from the mirror

characteristics of images formed by plane mirror

1. Image is virtual;
2. Same size as the object;
3. Same orientation as the object UPRIGHT laterally inverted
4. Same distance from the mirror as the object.

the sight testing chart

1) uses a plane mirror
2) letter chart should be 6m away from patient 3m testing room and plane mirror makes the total distance 6m
3) letters on chart are inversed so that they appear lateral to patient in mirror

what are the 2 types of mirror?

1) convex
2) concave

convex mirror

light rays will diverge

concave mirror

light rays will converge