© 2010 pearson education, inc. slide 25-2 25 electromagnetic induction and electromagnetic waves
TRANSCRIPT
© 2010 Pearson Education, Inc. Slide 25-2
25 Electromagnetic Induction and Electromagnetic Waves
© 2010 Pearson Education, Inc. Slide 25-4
© 2010 Pearson Education, Inc.
Induced Current in a Circuit
Slide 25-13
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Eddy Currents
Slide 25-35
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A changing magnetic field induces an electric field.
A changing electric field induces a magnetic field too.
Induced Fields
Slide 25-38
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Electromagnetic Waves
Slide 25-39
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Intensity of an Electromagnetic Wave
Slide 25-42
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Polarization
Slide 25-44
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Light passed through a polarizing filter has an intensity of 2.0 W/m2. How should a second polarizing filter be arranged to decrease the intensity to 1.0 W/m2?
Example Problem
Slide 25-45
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The Electromagnetic Spectrum
Slide 25-46
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The Photon Model of Electromagnetic Waves
Slide 25-47
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Thermal Emission Spectrum
Slide 25-50
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Hunting with Thermal Radiation
Slide 25-51
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Seeing the Universe in a Different Light
Slide 25-52
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Summary
Slide 25-54
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3. Comparing infrared and ultraviolet, we can say that
A. infrared has longer wavelength and higher photon energy.B. infrared has longer wavelength and lower photon
energy.C. ultraviolet has longer wavelength and higher photon
energy.D. ultraviolet has longer wavelength and lower photon
energy.
Reading Quiz
Slide 25-9
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Answer 3. Comparing infrared and ultraviolet, we can say that
A. infrared has longer wavelength and higher photon energy.B. infrared has longer wavelength and lower photon
energy.C. ultraviolet has longer wavelength and higher photon
energy.D. ultraviolet has longer wavelength and lower photon
energy.
Slide 25-10
© 2010 Pearson Education, Inc.
Example Problems A gamma ray has a frequency of 2.4 X 1020 Hz. What is the energy of an individual photon?
A typical digital cell phone emits radio waves with a frequency of 1.9 GHz. What is the wavelength, and what is the energy of individual photons? If the phone emits 0.60 W, how many photons are emitted each second?
Slide 25-48