Light and all electromagnetic  waves can vibrate in many directions. Those that are vibrating in one 
direction -- in a single plane such as up and down -- are called polarized light. Those that are vibrating in more than one direction -- in more than one  plane such as both up/down and left/right -- are called unpolarized light.
Generally, unpolarized light can be considered to be vibrating in a vertical  and a horizontal plane. To polarize light, one can transmit the light through a  polariod filter which will only allow light of single polarity to pass. The 
resulting light will be polarized light of half intensity. If two polaroid filters are used and placed so that one is rotated 90 degrees to the other, no light will be able to pass.
Some polarization will also occur during reflection, refraction, and scattering of light. When reflecting off non-metallic surfaces, the resulting light will be polarized parallel to the reflected surface. During refraction, a beam of light will be split up into two polarized beams, one polarized parallel and one perpendicular to the boundary. Scattering also causes partial polarization.

•HOOK:
Teacher reviews the last week’s lesson on
Electromagnetic
Radiation by discussing the exit question from the last
lesson.
Student watch Youtube video on Polariation of
light.http://www.youtube.com/watch?v=E9qpbt0v5Hw

ACTION:
Discuss
the lessons learn from the Youtube video.
Discuss polarization
of light in detail giving special emphases are giving to:
- generating waves
with special polarization
- polarization by Selective Absorption
-
Polarization by Reflection
- Polarization by Scattering
- Optical activity
and Liquid crystal display (LCD)

•CONSOLIDATION:
Teacher set up an
experiment for students to observe Polarization from Reflection using a bright
light source and two polaroid filters.
Students are to Perform the
experiment, Observe, Analyze and Communicate their findings in their report
sheets. Rubric is given by the
teacher..


 
 
 
 
Picture
    FIG: Electromagnetic wave

Picture
      FIG: One-way polarization

Picture
  FIG: Two-way polarization












 





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