CHAPTER-17%20Light%20and%20Image%20Formation

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CHAPTER-17 Light and Image Formation
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Chapter Outline
1 Reflection and Image Formation 2 Refraction
of Light 3 Lenses and Image Formation 4
Focusing Light with Curved mirrors 5 Eyeglasses,
Microscopes, and Telescopes Everyday Phenomenon
Rainbows and Laser Refractive Surgery
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How Does an Image Formed in a Mirror?
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How Are Light Rays Related to wavefronts?
Wavefronts are perpendicular to the rays.
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Reflection
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The Law of Reflection
The angle of incidence The angle of reflection.
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How Are Images Formed by a Plane Mirror?
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How Are Images Formed by a Plane Mirror?
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Q7
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Refraction of Light
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Definition Of The Index Of Refraction
The index of refraction n of a material is the
ratio of the speed c of light in a vacuum to the
speed v of light in the material
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Law of Refraction
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Apparent Depth of Fish Is Smaller Than Actual
Depth Due to Refraction
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Total Internal Reflection
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Why a Diamond Sparkles?
Why does a diamond exhibit such brilliance? And
why does a diamond lose much of its brilliance
when placed under water?
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Optical Instruments
Many optical instruments, such as binoculars,
periscopes, and telescopes, use glass prisms and
total internal reflection to turn a beam of light
through 90 or 180.
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Prism and Spectrum of Colors
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Dispersion of Light
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Rainbow
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Primary Rainbow
Water droplet disperses the light into colors.
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Secondary Rainbow
Colors are reversed and less intense.
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Focal Point (F) and Focal Length (F)
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Ray Diagram
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Ray Diagram
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Diverging or Negative lensFocal Point (F) and
Focal Length (f)
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Ray Diagram for Diverging Lens
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Lens Equation
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Lens Equation and Magnification, m
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E6
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Optical Instruments

• Human eye
• Camera
• Eyeglasses
• Microscope
• Telescope

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Vision Defects

• Nearsightedness can see only nearby objects
  clearly.
• Farsightedness can see only far objects clearly.

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Nearsighted Eye, Myopia
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Negative Lens Is Used to Correct Nearsightedness
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Positive Lens Is Used to Correct Farsightedness
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How Does a Microscope Work?

• Used to view small things nearby.
• Consists of two positive lenses, objective and
  eyepiece.
• Final image is magnified and inverted.
• Ray diagram can be used to illustrate the image
  formation.

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Ray Diagram For Microscope
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Microscope
A laboratory microscope has 3 or 4 objective
lenses.
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Astronomical Telescope
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LASIK