Reflection of Light The bouncing off of light

Reflection of Light The bouncing off of light as it hits a surface

Types of Reflection • Regular Reflection – a. k. a. specular reflection – When parallel rays are reflected parallel – Reflecting surface is smooth

Regular Reflection

Types of Reflection • Irregular Reflection – a. k. a. diffuse reflection – When parallel rays are reflected in different directions – Reflecting surface is not perfectly smooth

Irregular Reflection

Important Terms • Object – The source of light • Image – The picture of the object that is formed from the reflected rays

Important Terms image object

Important Terms • Incident Ray – Light ray that hits a surface • Reflected Ray – Light ray that bounces off the surface • Normal – Line that is perpendicular to the reflecting surface

incident ray normal reflected ray mirror

Important Terms • Angle of incidence – Angle between the normal and the incident ray • Angle of reflection – Angle between the normal and the reflected ray

incident ray Angle of incidence Angle of reflection normal reflected ray mirror

Investigation

Laws of Reflection #1 The angle of incidence equals the angle of reflection.

Laws of Reflection #2 The incident ray, the reflected ray and normal all lie in the same plane. This means they can all be drawn on a flat sheet of paper.

Ray Diagrams for Plane Mirrors Virtual Image

Virtual Image • Image formed by rays which seem to come from it but do not pass through it • Cannot be produced on a screen

Ray Diagrams for Plane Mirrors Same Distance

Ray Diagrams for Plane Mirrors Same Size

Ray Diagrams for Plane Mirrors

Ray Diagrams for Plane Mirrors Laterally inverted Left and right are interchanged !

Lateral Inversion When left and right are interchanged

Properties of the Image • Virtual • Object distance equals image distance • Same size • Laterally inverted

Seeing and Ray Diagrams

Seeing and Ray Diagrams

Ray Diagrams for Plane Mirrors When the eye is above the object

Ray Diagrams for Plane Mirrors When the eye is behind the object

Ray Diagrams for Plane Mirrors When the eye is in front of the object

Ray Diagrams for Plane Mirrors

Uses of Reflection • Reflectors for bikes and roads

Uses of Reflection • Reflectors for photography

Uses of Reflection • Rear-view mirrors

Uses of Reflection • Medical mirrors • Telescopes