Ch. 19: Reflection, Absorption, and Refraction of Light

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Ch. 19 Reflection, Absorption, and Refraction of
Light

• Vocabulary
• reflection, absorption, transmit, refraction

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When Light Strikes an Object

• Light travels in a straight line.
• It will continue moving in a straight line, until
  it hit something.
• Depending on what it hits, light may behave in
  very different ways.

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Reflection

• When light bounces off a surface, it is called
  reflection.
• When light is reflected it travels in a straight
  line away from the reflecting surface.
• Example of Reflection
• http//www.openschool.bc.ca/elementary/science4/h
  tml/bouncingLight.htm

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Absorption

• Any time light hits a surface, some of it is
  absorbed, or taken in.
• When light is absorbed into a surface it is
  transformed from light energy, into heat energy.
• That is why on a sunny day it is cooler to wear a
  white t-shirt, than a black t-shirt dark
  surfaces absorb more light than lighter surfaces.

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Refraction

• Some materials transmit light, or allow light to
  pass through them.
• These transparent materials cause light to bend
  as it is passing through the surface.
• When the light bends, it makes things look like
  they do not match up.

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Questions About Chapter 19

1. Which color absorbs the most light?
2. When light bounces off a surface, what is it
   called?
3. Describe what happens to light when it passes
   through glass or water.
4. What happens to a material when it absorbs light?
5. On a summer day, why is blacktop so much hotter
   than the dirt next to it?