Behavior of Light Light Light is energy traveling
Behavior of Light
Light: • Light is energy traveling in a wave-like manner • Light does not need a substance to travel through so it can travel through space. • Light is the part of the electromagnetic spectrum that humans can see
Electromagnetic Spectrum? We do not see these parts We see this part We do not see these parts
How do we see? • Without light there is no “sight” • Our eyes let in light and our brains interpret the images • We see light as brightness if it enters our eyes directly Luminous Object
How do we see? • More commonly, we see “reflected” light • Light can reflect (bounce off) objects and that light enters our eyes Luminous Object Light Reflection Illuminated Object
How do we see color? • White light can be split into different colors: Red Orange Yellow Green Blue Indigo Violet
How do we see color? • When white light shines on an object - some colors are absorbed, some colors are reflected • We only see “reflected” light colors • Absorbed light turns into heat
How do we see color?
How do we see color?
How do we see black? • If all the colors are absorbed, we don’t see any colors – we see black • Black is an absence of color
How do we see white? • If all the colors are reflected, we see white • White is an all the colors together All colors of light reflected = white
How do we see? • Light enters the pupil of the eye through a clear lens called the cornea • The light is focused on the retina in the back of the eye • The brain makes sense of the light and creates virtual images that make sense to us
Videos: • • Basics: https: //www. youtube. com/watch? v=9 Vsl 0 Iom 3 S 0 Why Indigo? : https: //www. youtube. com/watch? v=bf 7 WT 6 TLy 8 s • • • Old School: https: //www. youtube. com/watch? v=WLV 54 p. DJy. F 0 How we see: http: //www. scientificamerican. com/video/how-do-we-see-brain-basics-2 video/ Origins of Color Vision https: //www. youtube. com/watch? v=8 b. ZXM 0 p 5 JFQ • https: //www. youtube. com/watch? v=2 hzq. Thfl-7 U
Wave Behavior: • Reflection – when wave energy is not able to enter a new medium and is redirected • Refraction –when waves change direction upon entering a new medium • Diffraction – when waves spread out around a barrier
Reflection: new medium
Reflection Animation • http: //www. freezeray. com/flash. Files/Mirror. htm • http: //www. freezeray. com/flash. Files/Reflection 1. htm
Refraction: new medium
Refraction Animation • http: //www. freezeray. com/flash. Files/Glass. Block. htm • http: //www. upscale. utoronto. ca/PVB/Harrison/Flash/Optics/Refraction/R efraction. html
Refraction Demo:
Diffraction: waves
Diffraction of Sound
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