Behavior of Light

Light and Materials

• Without light, nothing is visible• Materials can be transparent, translucent and

opaque• Each type of material will affect the behavior

of light in different ways

Transparent, Translucent and Opaque

• A transparent material transmits light which means it allows most of the light to pass through

• Examples: water or window• A translucent material scatters light• Examples: glycerin soap or frosted window• An opaque material absorbs or reflects all

of the light that hits it• Examples: wooden desk, metal chair, most

materials are opaque

Light

• When light strikes a material it can be transferred to the matter

• The light is reflected, absorbed or transmitted• When the light is transmitted it can be

refracted, polarized or scattered

Reflection

• An image is a copy of an object formed by reflected(or refracted) waves of light

• Regular reflection occurs when parallel light waves hit a surface and reflect all in the same direction

• Regular reflection occurs when light hits a smooth, polished surface ex. A still lake

Diffuse Reflection

• A diffuse reflection occurs when parallel light waves strike a rough, uneven surface and reflect in many different directions

• This occurs when light reflects a rough lake and you see a blurred image

Refraction• A light wave will bend or refract when it

passes at an angle from one medium to another

• Refraction will make objects under water seem larger and closer

• Refraction can also cause a mirage which is a false or distorted image

Polarization

• Light with waves that vibrate in only one plane is polarized light

• A horizontal polarizing filter stops waves on a vertical plane

• A vertical polarizing filter stops waves on a horizontal plane

• Polarized sunglasses have vertically polarized filters to block horizontal light

Scattering

• Scattering means that light is redirected as it passes through a medium

• Scattering makes reddens the sun at sunrise and sunset

• The blue and green light has been scattered so the orange and red are the colors we see

• The sky is blue since the Earth’s atmosphere scatters the blue light in all directions, the air is actually colorless