Interactions of Light With Matter Science: Chapter 3 Mrs. Milliken

 Reflection is the bouncing back of light rays when they hit an object.  The Law of Reflection states that an angle of incidence is EQUAL to the angle of reflection.

The Law of Reflection  What makes us see our reflection?

The Law of Reflection  The beam of light toward the mirror is the INCIDENT BEAM.  The middle line is the NORMAL Line  The beam of light away from the mirror is the REFLECTED BEAM

Regular vs. Diffuse Reflection  Regular reflection occurs when a light beam is reflected at the same angle.  Diffuse Reflection occurs when light beams reflect at many different angles, like when light hits a wall.

Absorption  Absorption is when energy from light waves are transferred to matter.  For example this causes a flashlight beam to get dimmer the farther away from the flashlight.

Scattering  Scattering occurs when light energy is released from particles that have extra energy.  This affects light with short wavelengths  For example: This is what causes the sky to look blue.

Transmission  Transmission occurs when glass or other transparent material transmits light to pass through.  When light is transmitted from one material to another it changes speed and this causes the light to bend, called refraction.

Transparent, Translucent and Opaque  Transparent: visible light is easily transmitted (glass).  Translucent: transmits light through but scatters it (frosted window).  Opaque: cannot see through the object, it will absorb and reflect light.

Colors  We see colors because the wavelengths of visible light are reflected off an opaque object.