BEHAVIORS OF WAVES

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BEHAVIORS OF WAVES

• Standard 8-6.4
• Summarize the behaviors of waves (including
  refraction, reflection, transmission and
  absorption).

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VOCABULARY WORDS
4 Ways that waves interact
1. Reflection When a wave hits a surface through
which it cannot pass, it bounces back.
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2. Refraction Is the bending of a wave as it
moves from one medium into another medium at an
angle, it changes speed as it enters the second
medium, which causes it to bend.
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3. Transmission

• Occurs when waves pass through a given point or
  medium.
• example Sound waves transmitted thru solids,
  liquids and gases. Radio waves are transmitted
  through one electron through another.
• Light waves are transmitted 3 ways light and
  matter can pass through material.
• A. Transparent material Only a small amount
  of light is reflected or absorbed (may be clear
  or colored material such as filters, windows).

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• B. Opaque material allows no light waves to be
  transmitted through them.
• C. Translucent materials Transmit some light,
  but cause it to be scattered so no clear image is
  seen.

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4. Absorption

• - Occurs when the energy is not transferred
  through or reflected by the given medium
• Disappearance of an electromagnetic wave into a
  medium.
• Opposite of reflection
• We see colors because of the selective absorption
  of visible light.
• Objects absorb certain wavelengths and we see
  what is leftover.
• The colors we see depend on the wavelength
  absorbed.

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Absorption
Yellow
Green
Red
Blue
Red
Orange
Violet
The apple absorbs all wavelengths except red.
The apple reflects mostly red. Therefore, it
looks like red.
Essay question on test!!!
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Absorption

• A material that absorbs all wavelengths of
  visible light will appear black.
• In contrast, a material that reflects all
  wavelengths will appear white.
• Objects or substances that absorb any wavelength
  of EM radiation become warmer and convert the
  absorbed energy to infrared radiation.
  (GREENHOUSE EFFECT)

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1. WHAT ARE THE 4 WAYS WAVES WILL INTERACT?
Reflection Refraction Transmission Absorption
2. WHAT ARE THE 3 WAYS LIGHT AND MATTER CAN PASS
THROUGH?
Transparent Opaque Translucent
3. WHAT IS THE COLOR WHITE AND THE COLOR BLACK?
White is all color reflected Black is all color
absorbed
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• Wave video Properties of Waves

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WAVE MOVEMENTS ANDEM WAVES
INTERFERENCE When two or more waves are moving
through a medium at the same time.
-The energy of the waves may interact by adding
together or canceling out as they pass. (Tsunami
waves) - Once the waves have passed each other,
they continue unchanged by the interaction.
http//physics-animations.com/Physics/English/int_
txt.htm
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Interference

• Constructive Interference When two waves
  combine to make a wave with larger amplitude.
• Helping each other
• Destructive Interference When the amplitude of
  two waves combine with each other producing a
  smaller amplitude.

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DIFFRACTION Is the scattering of a wave as it
hits the edges of a boundary or tiny opening. The
wave will try to curve around the boundary or
outward through the opening.
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EM (Electromagnetic Waves)

• How do electromagnetic waves differ from
  mechanical waves?
• EM waves do NOT need a medium to travel through.

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EM Waves

• Every time you feel the suns heat, listen to
  your MP3 player, or pop a bag of popcorn in the
  microwave, you are using a different form of the
  electromagnetic energy.
• EM waves make these events possible.

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EM Waves

• EM waves are transverse waves that have some
  electrical properties and some magnetic
  properties.
• It consists of changing electric and magnetic
  fields.
• EM waves travel as vibrations in electric and
  magnetic fields.

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EM Waves

• EM waves vary based on wavelength, energy and
  frequency.
• Electromagnetic energy is created by vibrations
  (just like mechanical waves).
• This produces waves that carry the energy.
• Each EM wave emits at different energy levels.
• The collection of all EM frequencies is known as
  the Electromagnetic Spectrum.

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Electromagnetic Spectrum
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Electromagnetic Spectrum

• 1. Radio waves are used to transmit radio and
  television signals. Radio waves have wavelengths
  that range from less than a centimeter to tens or
  even hundreds of meters.
• Longest wavelength, lowest frequency and least
  amount of energy.
• They travel long distances by reflecting their
  signals off Earths atmosphere or off satellites.

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Electromagnetic Spectrum

• 2. Microwaves shorter wavelengths, higher
  frequencies, and more energy than radio waves.
• Cell phones and radar are two uses of microwaves.
• 3. Infrared Light - is the region of the
  electromagnetic spectrum that extends from the
  visible region to about one millimeter (in
  wavelength). Infrared waves include thermal
  radiation.
• Associated with heat

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Electromagnetic Spectrum

• 4. Visible Light The range of EM waves that can
  be detected by the human eye.
• Longest wavelength is of visible light is red.
• Shortest wavelength of visible light is violet.
• The color we see is determined by the way the
  light interacts with the object.
• How it is reflected and how it is transmitted.
• 400 700 nm (nanometers)

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Visible Light
Each of these colors actually corresponds to a
different wavelength of light.
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How Roy G. Bv Lost a Vowel The sequence of colors
red, orange, yellow, green, blue, and violet may
be remembered by memorizing the name of that fine
fellow "ROY G. BV". This was originally "ROY G.
BIV", because it used to be common to call the
region between blue and violet "indigo". In
modern usage, indigo is not usually distinguished
as a separate color in the visible spectrum thus
Roy no longer has any vowels in his last name.
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Electromagnetic Spectrum

• 5. Ultraviolet Light (UV)- Higher frequency than
  visible light and carry more energy.
• Can damage or kill living cells
• Tan skin by the sun or tanning bed

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Electromagnetic Spectrum

• 6. X-rays - high energy waves which have great
  penetrating power and are used extensively in
  medical applications and in inspecting welds. The
  wavelength range is from about ten billionths of
  a meter to about 10 trillionths of a meter.
• Short wavelengths and high frequencies allow them
  to travel through skin, but not bone (more dense)

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Electromagnetic Spectrum

• 7. Gamma Rays Shortest waves, with the highest
  frequency (and highest energy).
• They are more penetrating than X-rays
• Can kill living cells
• Used to sterilize medical equipment

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How do prisms separate visible light?

• When light shines through a prism, the glass
  changes the behavior of each light wave according
  to the wave's wavelength.
• This property of glass is known as its refractive
  index.
• The prism changes the direction the light is
  traveling.
• As a result, what goes in as ordinary white light
  comes out separated into a spectrum of different
  colors.
• That's because white light is really all those
  wavelengths mixed together.

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Visible Light
Each of these colors actually corresponds to a
different wavelength of light.
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How Roy G. Bv Lost a Vowel The sequence of colors
red, orange, yellow, green, blue, and violet may
be remembered by memorizing the name of that fine
fellow "ROY G. BV". This was originally "ROY G.
BIV", because it used to be common to call the
region between blue and violet "indigo". In
modern usage, indigo is not usually distinguished
as a separate color in the visible spectrum thus
Roy no longer has any vowels in his last name.