Transcript How do eye glasses work? BUT first, let`s review!

How do eye glasses
work?
BUT first, let’s review!
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What is energy?
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Can energy be created?
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no or destroyed, it can only be transformed from one
form into another
What is kinetic energy?
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The capacity for doing work (or to produce heat)
(KE) refers to the energy associated with the motion
of an object.
What is potential energy?
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An object can store energy as the result of its position
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What is a transverse wave?
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What is a longitudinal wave?
 The particles of the medium vibrate back
and forth along the path that the wave
moves.
What is the equation to find velocity?
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A wave in which the particles of the medium move
perpendicularly to the direction the wave is
traveling.
V= λ * f
What are EM waves?
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They are Transverse waves without a medium.
They travel as vibrations in electrical and
magnetic fields.
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List the EM Spectrum from longest
wavelength to shortest.
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What is the speed of light?
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Angle of incidence = Angle of reflection
What is refraction?
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3.0 X 10^8 m/s
What is the law of reflection?
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Radio, Microwave, Infrared, Visible, UV, X-Ray,
and Gamma
The bending of a wave as it passes at an angle
from one substance to another
What is diffraction?
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Bending of light around a barrier or small opening
Lenses: How do they work?
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Lens
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Transparent piece of glass or plastic that
refracts light in a predictable way
Diverging/Concave lens
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A concave lens causes light to diverge, or
spread out, making a smaller image
Concave Lens
Convex Lens
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A convex lens causes light to converge,
or focus, the type of image formed by a
convex lens depends on the position of
the object in relation to the focal point.
Notice, that
was what up
is down and
what was
down is up
after the focal
point
Essential Knowledge, Skills,
and Processes
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Identify some common optical tools, and
describe whether each has lenses, mirrors,
and/or prisms in it. These should include:
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eyeglasses
flashlights
cameras
binoculars
microscopes
Essential Knowledge, Skills,
and Processes
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Eyeglasses: have lenses
No correction needed
a. Normal eye
b. Myopia (nearsightedness) Corrected with concave lens
c. Hyperopia (farsightedness) Corrected with convex lens
Essential Knowledge, Skills,
and Processes
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Flashlight: has lenses and a mirror
Essential Knowledge, Skills,
and Processes
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Cameras: have lenses, mirrors, and a prism
Essential Knowledge, Skills,
and Processes
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Binoculars: have lenses and prisms
Essential Knowledge, Skills,
and Processes
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Microscope: has lenses
How have humans used science
to engineer technologies that use
electromagnetic energy?
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1. Use of lasers
Laser:
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Powerful energy of light due to concentrating one
wavelength (frequency)(color) of light
All energy is lined up
Lasers
On “same
wavelength” In
sync with one
another (laser)
Flashlight
Lasers
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Uses:
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Fiber optics
Surgery
UPC codes
Burning and reading CD’s, DVD’s &
optical flash drives