Chapter 13 Notes

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Chapter 13 Notes

• Electromagnetic Waves Page 388

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Section 1 What are electromagnetic Waves?

• Answer the following questions
• How do electromagnetic waves travel through
  space?
• How do electromagnetic waves transfer energy to
  matter?

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• Page 332
• Parts of a wave
• I. Transverse Waves have
• A. Troughs low points
• B. Crests high points
• Demo

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II. Compressional Waves Have

• Rarefactions less dense / less compact regions.
• Compressions dense / compact regions.
• Demo

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Wavelength

• For Transverse Waves distance from one crest to
  the next or from one trough to the next.

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II. For Compressional Waves

• Wavelength is the distance from one rarefaction
  to the next or from one compression to the next.
• Frequency number of wavelengths that pass a
  fixed point each second measured in units called
  hertz (Hz) 1 wavelength per sec.

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Amplitude and Energy

• Amplitude distance from rest position to the
  crest or trough in a transverse wave.
• For a compressional wave, amplitude is related
  to how dense the compressions are more dense
  higher amplitude.
• The greater a waves amplitude, the more energy
  it carries.

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Wave Speed

• Wave Speed wavelength x frequency
• v ? x f
• v
• ? f

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Calculating speed, wavelength and frequency

• To calculate wave speed (v)
• v cover up v
• ? f
  ? f
• Multiply ? and f to calculate wave speed (v).

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Calculating speed, wavelength and frequency,
continued

• To calculate wavelength (?)
• v cover up ? v
• ? f
  f
• Divide v by f to calculate wavelength (?).

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Calculating speed, wavelength and frequency,
continued

• To calculate frequency (f)
• v cover up f v
• ? f
  ?
• Divide v by ? to calculate frequency (f).

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Section 3 Behavior of Waves

• Page 339
• Reflection light waves bouncing off of an
  object.
• Refraction bending light waves in a material,
  such as water, due to the waves slowing down.
• Diffraction bending light waves around an
  object.

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Section 3 Continued

• Interference when two or more waves combine to
  form a new wave.
• Constructive the wave amplitudes add together.
• Destructive wave amplitudes subtract from each
  other.
• Standing Waves equal waves traveling in
  opposite directions.

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Nodes

• Places where two standing waves cancel each other
  out (Figure 23, page 346).
• Resonance the ability of an object to vibrate
  by absorbing energy.
• Demos

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Chapter 11 Test Review

• Wave Speed
• Reflection
• Amplitude
• Seismic wave
• Node
• Medium
• Diffraction
• Frequency

• Fill-in-the-blanks (terms)
• Wave
• Refraction
• Wavelength
• Crest
• Rarefaction
• Transverse wave
• Interference

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Trough Compression Compressional wave Standing
wave Resonance Angle of incidence Angle of
reflection Normal
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Matching

• Wavelength
• Frequency
• Wave Speed

• Meter
• Meters / second
• hertz

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Know the differences among the following terms

• Refraction, reflection, and diffraction
• Transverse, compressional, and seismic waves
• Seismic, tidal, and uniform waves
• Wave speed, wavelength, and frequency
• Antinode, node, and compression

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Questions

• How do particles move differently in transverse
  waves and in surface water waves?
• Be able to identify and explain the differences
  between transverse waves and compressional waves.
• Why dont all loud sounds cause glass objects to
  break?

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Questions, continued

• Be able to answer a question about light waves
  passing through a piece of glass at an angle.
• In a standing wave, what kind of interference
  produces the crests and the nodes?

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Be able to label the parts of a wave
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Calculation

• Use the wave speed equation to calculate the
  speed, frequency, and wavelength of a wave (You
  can use a note card)
• Wave Speed wavelength x frequency
• v ? x f
• v
• ? f

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More Questions

• How do we get moon light?
• How do you know that light is a type of wave that
  can travel with out a medium (matter)?
• Be able to explain what happen to amplitude,
  frequency, and wavelength of a wave when one of
  them changes.
• Be able to answer a question about refraction.

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More Questions, Continued

• Be able to answer a question about interference.
• Be able to answer a question about reflection.
• Be able to answer a question about frequencies in
  standing waves.