Reflection and Color

Chapter 15.3

Light modeled as a ray • Light ray a line in space that matches the

direction of the flow of radiant energy• (Imaginary line running in the direction that

light travels) • Used to show reflection, diffraction, and

refraction

Reflection from different surfaces…• Rough surfaces reflect light in many directions• Smooth surfaces reflect light in the same

direction

• Angle of incidence the angle that the light ray strikes a surface

• Angle of reflection the angle that the light ray reflects off a surface

Law of Reflection

• The incoming and outgoing angles are measured from a perpendicular line to the surface (“the normal line”)

• Law of Reflection the angle of incidence is equal to the angle of reflection

Mirrors• Flat mirrors form virtual images by reflection• Virtual image an image that forms at a

location from which light rays appear to come, but do not actually come

• You are not actually behind the mirror, you just appear to be!...hence, virtual image

Curved Mirrors

• Curved inwards = concave • Curved outward = convex • Curved mirrors create

distorted images! (stretch and compress parts of images since the surface is not smooth)

Concave Mirrors• Mirrors that bow

outwards• Concave mirrors create

real images an image of an object formed by rays that actually come together at a specific location

Seeing Colors• An object is the color that is REFLECTS…it

absorbs all other colors (objects have color because they reflect certain wavelengths)

• Green grass is not green green is the color that grass cannot absorb, so it reflects it (therefore we see the green!)

Adding and Subtracting Colors• Mixing all colors together = white color • The absence of color = black • Black hole where time and space break down?

A few color illusions• http://www.planetperplex.com/en/item/checker

-shadow/

• http://www.planetperplex.com/en/item/false-color/

• http://www.planetperplex.com/en/item/are-you-color-blind/

• http://colorvisiontesting.com/online%20test.htm • http://www.michaelbach.de/ot/mot_spokes/ind

ex.html

• http://www.illusion-optical.com/Optical-Illusions/ColorReading.php