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You...
Light up.....
my life
https://www.youtube.com/watch?v=50B8ErvdElI
To understand the properties of light...
1. It is a form of energy!...(I can prove it!)
2. How it is produced
3. How it travels
4. How it interacts with objects
Light
...is a form of energy because it has the
ability to do work
Ex: When light energy from the sun hits a black shirt it begin to
heat the shirt because light energy is turned into thermal
energy
Energy is neither created or destroyed...it simply
changes forms
Review ******
Producers turn light energy into chemical energy which
consumers eat and turn into sound energy...thermal energy and
kinetic energy
herbivores carnivores omnivores
Plants
Sun
How is light made...ON THE MOVE...Let me explain!!!
Protons---carry a positive charge and found in
nucleus
electrons---carry a
negative charge and
found in outside
orbits
Nucleus---center of atom
Neutrons---carry no charge and found in nucleus
Electrons...jump orbits and when they do they release
energy which we see as a burst of light...Photons
Travels in straight line
And...its fast...186,000 miles per second
Sun light leaving our star reaches us in 8 minutes
Are all objects visible?
ONLY.... if reflection or refraction occurs
Another REVIEW !!!!
To understand how light interacts
with objects it encounters
Reflection.....
So.... why do I see colors?
Fact #1 we see white light when all the colors of the spectrum
are reflected back into our eyes
Fact # 2
You see colors ...when white light hits an object and all the
colors are absorbed except for the color which you see---that
color is reflected by the object and comes back to your eye.
So red objects reflect red --- orange objects reflect orange --green reflect green .... etc
white light
red
green
all other colors are absorbed
Fact #3
white light
All the colors are absorbed and nothing is
reflected back to the eye
Reflection is when light bounces off an object. If the
surface is smooth and shiny, like glass, water or
polished metal, the light will reflect at the same
angle as it hit the surface.
Reflection involves a change in direction of waves
when they bounce off a barrier. Refraction of waves
involves a change in the direction of waves as they
pass from one medium to another. Refraction, or
the bending of the path of the waves, is
accompanied by a change in speed and wavelength
of the waves.
2
Refraction causes the rainbow effect