Waves Ch 17

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Waves Ch 17

• Behavior of Waves

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I. REFLECTION
LIGHT
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A. Reflection

• Occurs when a wave strikes an object and bounces
  off of it.
• Light waves
• a. light bounces off the moon and is reflected
  back to your eye.
• b. Light strikes your face and bounces off, hits
  the mirror, and is reflected into your eyes.
• Sound waves
• a. Echo is a sound hitting an object and being
  reflected back to you.

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A. Reflection
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I. REFLECTION

• 4.The law of reflection the angle of incidence
  is equal to the angle of reflection (occurs with
  both mechanical and electromagnetic waves)

mirror
r
normal
i
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B. Interference

• Ability of 2 or more waves to combine and form a
  new wave
• Waves pass through each other and continue in
  original direction.
• Occurs when two waves combine into one

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• 4.Types of Interference
• a. Constructive the wave gets bigger because the
  crests and troughs overlap waves add together
• b. Destructive the wave gets smaller because a
  crest and a trough overlaps waves subtract from
  each other

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IV. INTERFERENCE
when two or more waves (mechanical and
electromagnetic) overlap and combine to form a
new wave a. constructive interference waves
are added together
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B. Interference

• Light waves
• a. Constructive brighter light
• b. Destructive - dimmer light
• Sound waves
• constructive produces much louder sounds
• Destructive produces softer sound

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C. Refraction

• Bending of a wave caused by a change in its speed
  as it moves from one medium to another
• Ex pencil in a cup Light slows down as it
  goes from air to water and the wave gets bent

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C. Refraction
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II. REFRACTION
the bending of light waves caused by a change
in its speed as it moves from one medium to
another.
Light goes from a liquid to a gas so it speeds up
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D. Diffraction

1. Object causes a wave to change direction and bend
   around it.
2. Ocean waves change direction and bend when they
   strike an island

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D. Diffraction
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III. DIFFRACTION
Diffraction the bending of waves around a
barrier or a narrow opening.