PHY138 Waves Lecture 9 Quarter Review, including:

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PHY138 Waves Lecture 9Quarter Review,
including

• Simple Harmonic Motion Force, Energy
• Mass on spring / Pendulum
• Damped Oscillations, Resonance
• Traveling Waves, Power and Intensity
• Standing Waves, Interference, Beats
• Ray Model of Light, Ray-Tracing
• Reflection, Refraction of Light

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Tomorrow evening, 600 PM

• It is mandatory that you go to the room assigned
  to your tutorial group.
• You should have no communication device (phone,
  pager, etc.) within your reach or field of vision
  during the test.
• The test has eight equally weighted
  multiple-choice questions (8 marks each).
• The test has one multi-part problem counting for
  36 marks show your work.

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Dont forget

• Your student card.
• A non-programmable calculator without text
  storage and communication capability.
• A single original, handwritten 22 28 cm sheet
  of paper on which you have written anything you
  wish on both sides. We will supply any numerical
  constants you might need.
• A dark-black, soft-lead 2B or 2HB pencil with an
  eraser.

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Some more words to the wise

• A good aid-sheet is well organized, easy to read,
  and contains all the major equations from the
  assigned sections from the reading.
• Copies of detailed specific problem solutions are
  unlikely to help.
• Be ready to think get a good nights sleep
  tonight.
• Keep in mind Your best 3 out of 4 tests will
  count for 30 of your mark in the course.

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The Eye
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Mass on Spring versus Pendulum
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14.7 Damped Oscillations
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Snapshot Graph
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History Graph
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Sinusoidal Wave Snapshot Graph

• k 2p/? is the wave number

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Sinusoidal Wave History Graph

• ?2p/T is the angular frequency

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Sound Waves can be described either by the
longitudinal displacement of the individual
particles, or by the air or fluid pressure.
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Electric and Magnetic fields, when oscillated,
can create waves which carry energy. At certain
frequencies, we see electro-magnetic waves as
Light.
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Power and Intensity

• The Power, P, of any wave source is how much
  energy per second is radiated as waves units
  Watts
• The Intensity, I, is the energy rate per area.
  This determines how loud (sound) or bright
  (light) the wave is.
• IP/a, where a is an area perpendicular to the
  wave direction.
• At a distance r from a small source, the
  intensity is IP/(4pr2)

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Doppler Effect
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Principle of Superposition

• If two or more waves combine at a given point,
  the resulting disturbance is the sum of the
  disturbances of the individual waves.
• Two traveling waves can pass through each other
  without being destroyed or even altered!

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Standing Wave
The superposition of two 1-D sinusoidal waves
traveling in opposite directions.
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Harmonic frequencies of Standing Waves

• Transverse standing wave on a string clamped at
  both ends there are nodes in displacement at
  both ends.

Standing sound wave in a tube open at both ends
there are nodes in pressure both ends.
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Wave Interference

• Two waves moving in the same direction with the
  same amplitude and same frequency form a new wave
  with amplitude

where a is the amplitude of either of the
individual waves, and is their phase
difference.
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Beat frequency

• Beats are loud sounds separated by soft sounds
• The beat frequency is the difference of the
  frequencies of the two waves that are being added

• The frequency of the actual sound is the average
  of the frequencies of the two waves that are
  being added

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The Law of Reflection
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Snells Law of Refraction
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Total Internal Reflection

• Can only occur when n2ltn1
• ?c critical angle.
• When ?1 ?c, no light is transmitted through the
  boundary 100 reflection

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Virtual Image Formation by Reflection
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Virtual Image Formation by Refraction
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Real Image Formation with a Converging Lens
Focal length, f
Real Image (inverted)
Object