Physics 123C Waves

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Physics 123C Waves
Review 3 (for Final Exam)Chapters
14,20,21,22,23,24,34,37,38 June 3, 2005

• John G. Cramer
• Professor of Physics
• B451 PAB
• cramer_at_phys.washington.edu

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Lecture Schedule (Weeks 7-10)
We are here
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Review 3 Announcements

• If you have not already done so, register your
  Clicker using the link on the 123C Syllabus page
  as soon as possible.
• You are required to complete the Tycho Course
  Survey by 1159 PM on June 5. Please complete it
  as soon as possible.
• The Final Exam will be in this room at 830 AM
  on Monday, June 6. (NOT at 1030 AM!) You may
  bring to the Final 3 pages of notes. Also bring
  a Scantron sheet and a calculator with good
  batteries. The Final is worth 150 points. It
  will be comprehensive, with Lecture, Tutorial,
  Tycho, and Lab sections.
• Before you come to the Exam on Monday, check
  for seat assignments on Tycho. Special requests
  for seats (left handed, aisle, front) should be
  sent to me by E-mail.

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Exam 3 Statistics
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Chapter 14 Summary (1)
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Chapter 14 Summary (2)
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Chapter 14 Summary (3)
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Example The MaximumAngle of a Pendulum
A 300 g mass on a 30 cm long string
oscillates as a pendulum. It has a speed of 0.25
m/s as it passes through the lowest point.
What maximum angle qmax does the pendulum have?
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Chapter 20 - Summary (1)
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Chapter 20 - Summary (2)
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Chapter 20 - Summary (3)
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ExampleLight Traveling through Glass

• Orange light with wavelength 600 nm is incident
  on a 1 mm thick microscope slide.
• What is the speed of light in the glass?
• How many wavelengths of light are inside the
  slide?

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Example How Fast are the Police Traveling
A police siren has a frequency of 550 Hz as
the police car approaches you, 450 Hz after is
passes you and is receding. The temperature is
200C. How fast are the police traveling?
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Example Listening to Beats
One flutist plays a note of 510 Hz, while a
second flutist plays a note of 512 Hz. What
frequency do you hear? What is the beat
frequency?
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Chapter 21 - Summary (1)
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Chapter 21 - Summary (2)
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Chapter 21 - Summary (3)
Guitar, piano, violin
Open organ pipe
Closed organ pipe, Clarinet.
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Example Designing an Antireflection Coating
Magnesium fluoride (MgF2) is often used as
an antireflection coating on lenses. The index
of refraction of MgF2 is n 1.39. What is
the thinnest film thickness of MgF2 that works on
an antireflection coating for light with l 510
nm (near the center of the visible spectrum)?
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Example The Length of an Organ Pipe
An organ pipe open at both ends sounds its
2nd harmonic at a frequency of 523 Hz (one octave
above middle C). What is the length of the
pipe from sounding hole to end?
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Chapter 34 - Summary (1)
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Chapter 34 - Summary (2)
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Chapter 34 - Summary (3)
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Example The Electric Fieldof a Laser Beam
A helium-neon laser emits a 1.0 mm diameter
laser beam with a power of 1.0 mW. What is
the amplitude of the oscillating electric field
in the laser beam?
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Chapter 22 - Summary 1
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Chapter 22 - Summary 2
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Chapter 22 - Summary 3
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Example Diffraction of a laser through a slit
Light from a helium-neon laser (l 633 nm)
passes through a narrow slit and is seen on a
screen 2.0 m behind the slit. The first minimum
of the diffraction pattern is observed to be
located 1.2 cm from the central maximum. How
wide is the slit?
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Chapter 23 Summary (1)
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Chapter 23 Summary (2)
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Chapter 23 Summary (3)
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Example Finding theimage of a flower
A 4.0 cm diameter flower is 200 cm from the
50-cm-focal-length lens of a camera. How far
should the film be placed behind the lens to
record a well-focused image? What will be
the diameter of the image on the film?
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Chapter 24 Summary (1)
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Chapter 24 Summary (2)
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Chapter 24 Summary (3)
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Example The de Broglie Wavelength of an Electron
An electron (mass 9.11x10-31 kg) used in the
Davisson-Germer experiment has a speed of
4.35x106 m/s. What is the de Broglie
wavelength of such an electron?
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Chapter 37 - Summary (1)
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Chapter 37 - Summary (2)
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ExampleThe Speed of an Alpha Particle
Alpha particles usually are characterized by
their kinetic energy in MeV. What is the
velocity of an 8.30 MeV alpha particle?
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Chapter 38 - Summary (1)
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Chapter 38 - Summary (2)
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Chapter 38 - Summary (3)
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ExampleEmission and Absorption
An atom has only three stationary states E1
0.0 eV, E2 3.0 eV, and E3 5.0 eV. What
wavelengths are observed in the absorption
spectrum and in the emission spectrum of this
atom?
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Example Wavelength ofan Emitted Photons
An atom has stationary states with energies
Ej 4.0 eV and Ek 6.0 eV. What is the
wavelength of a photon emitted in a quantum jump
from state k to state j?
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End of Review 3

• If you have not already done so, register your
  Clicker using the link on the 123C Syllabus page
  as soon as possible.
• You are required to complete the Tycho Course
  Survey by 1159 PM on June 5. Please complete it
  as soon as possible.
• The Final Exam will be in this room at 830 AM
  on Monday, June 6. (NOT at 1030 AM!) You may
  bring to the Final 3 pages of notes. Also bring
  a Scantron sheet and a calculator with good
  batteries. The Final is worth 150 points. It
  will be comprehensive, with Lecture, Tutorial,
  Tycho, and Lab sections.
• Before you come to the Exam on Monday, check
  for seat assignments on Tycho. Special requests
  for seats (left handed, aisle, front) should be
  sent to me by E-mail.

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Constants