Waves

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Chapter 14

• Waves

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14.1 Types of waves

• What is a wave?
• A wave is a _________________________
• Most waves travel through a ____________
• A medium is ________________________

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14.1 Types of waves

• There are two basic types of waves
• Mechanical wave ______________
• Almost ______ waves are mechanical
• Electromagnetic (EM) wave _____________
• AKA a _________ wave

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14.1 Types of waves

• Light _________ require a medium. This allows the
  sun to transmit energy to the Earth through empty
  space.
• Visible light waves are just one example of light
  waves. Remember that light waves may refer to
  waves we cannot see like _________________________
  __________

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14.1 Types of waves

• Earlier you learned that energy can be defined as
  the ability to do work.
• We know that waves carry ____________ because
  they can do ___________
• Some examples are
• _______ waves moving a leaf , boat, or beach
• _______ waves moving your chest and eardrum

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14.1 Types of waves

• If you stand next to the speakers at a concert,
  the sound may damage your ears. Likewise, if you
  look at a bright light bulb from too close, the
  light may damage your eyes. But if you are 100
  meters away, the sound or light is harmless. Why?

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14.1 Types of waves

• Describe the waves created when a stone is
  dropped into a pond.
• The waves spread out in _________that get ______
  as the wave moves farther from the center.
• Each of these circles is called a
  __________________.

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14.1 Types of waves

• Each wave front has the ________ amount of total
  __________.
• But as the circles get _________, the energy
  spreads out over a larger area, giving it less
  ___________ in a single spot.
• When sound waves travel in ___, the waves spread
  out in ______, causing their energy to spread
  like the water waves.

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14.1 Vibrations and waves

• When a singer sings a note, the vocal cords in
  the singers throat move _____________.
• This motion make the air in the throat vibrate,
  creating _________________ that eventually reach
  your ears.
• The vibration of the air in your ears causes your
  ______________________.

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14.1 Vibrations and waves

• Most waves are caused by _______ objects.
• EM waves may be caused by vibrating
  _____________________.
• In mechanical waves the particles in the _______
  vibrate as the wave ____________ the medium

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14.1 Vibrations and waves

• Vibrations involve _____________ of energy
• What happens if you lift or pull on the mass
  pictured here?
• This is called ________________

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14.1 Vibrations and waves

• Waves can pass trough _______________________.
• _________________________________________.

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14.1 Vibrations and waves

• The motion of particles in a _______ is like the
  motion of the attached masses on springs
• As one particle _______________________

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14.1 Transverse and longitudinal waves

• Particles in a medium can either vibrate
  __________________________________.
• Waves are classified by the direction they move
  into three basic types

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14.1 Transverse waves

• Transverse wave
• Examples

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14.1 Longitudinal waves

• Longitudinal wave
• Examples

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14.1 Surface waves

• Waves in the ocean or a pool are
  __________________________________.
• They occur at the ________ between two
  ___________ mediums (i.e. ___________)
• The particles in a surface wave move both
  ____________________ to the direction of the wave
  giving it a _______ motion overall

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14.1 Surface waves
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14.2 Characteristics of waves

• All transverse waves have the same basic shape
• A sine wave looks like

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14.2 Parts of a transverse wave

• Crest
• Trough
• Amplitude
• Node

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14.2 Parts of a transverse wave
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14.2 Parts of a longitudinal wave

• Compression
• Rarefaction

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14.2 Parts for both waves

• Wavelength
• Period
• Frequency
• Frequency-Period Equation
• Frequency

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14.2 Wave speed

• Speed v
• How do we measure distance in a wave?
• How do we measure time in a wave?
• If we replace distance and time with our new
  measures we end up with
• Speed
• Now we can replace 1/t
  

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14.2 Wave speed equation

• Wave speed is
• Wave speed equation equals
• Wave speed
• v