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Characteristics of EM Wave. perpendicular to the direction of propagation. is perpendicular to. vary sinusoidally (transverse wave). gives the direction of wave travel. and. are in phase. Speed of wave: c :. http://www.colorado.edu/physics/phet/web-pages/simulations-base.html.
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Characteristics of EM Wave perpendicular to the direction of propagation is perpendicular to vary sinusoidally (transverse wave) gives the direction of wave travel and are in phase Speed of wave: c:
http://www.colorado.edu/physics/phet/web-pages/simulations-base.htmlhttp://www.colorado.edu/physics/phet/web-pages/simulations-base.html • Applications: • Radio • Television • Microwave oven
Electromagnetic Waves Light is a traveling wave of electric and magnetic fields (electromagnetic wave but created differently!).
Polarization of Light The electric field is always perpendicular to the direction of travel of the waves, Unpolarized light: the light consist of EMW with E-field oriented in many different directions. Polarized light: the light consist of EMW with E-field oriented in the same direction (can be resolved into two components). An electric field component parallel to the polarizing direction is passed by a polarizing sheet; a component perpendicular to it is absorbed
Polarization and Intensity Where is the intensity of light before polarization and is the intensity after polarization: A one-half rule (for an unpolarized light) A cosine-squared rule (for a polarized light)
Sample Problem #1 What is the wavelength of the electromagnetic wave emitted by the oscillator-antenna system of the figure if L = 0.253 μH and C = 25.0 pF?
Sample Problem #2 The figure shows a system of three polarizing sheets in the path of initially unpolarized light. The polarizing direction of the first sheet is parallel to the y axis, that of the second sheet is at an angle of 60o counterclockwise from the y axis, and that of the third sheet is parallel to the x axis. What fraction of the initial intensity I0 of the light emerges from the three-sheet system, and in what direction is that emerging light polarized?
Problem In the figure, a beam of unpolarized light, with intensity 43 W/m2 is sent into a system of two polarizing sheets with polarizing directions at angles and to the y axis. What is the intensity of the light transmitted to the system?