Light is a form of energy that is created from a different form of energy There are two types Incandescence Light from heat or high temperature Luminescence Light from electron giving off energy ID: 314641
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Slide1
What is light??Slide2
Light is a
form
of energy that is created from a different form of energy
There are two types
Incandescence
- Light from heat or high temperature
Luminescence
–Light from electron giving off energy
https://www.youtube.com/watch?v=
YnMP1Uj2nz0
What are the source of light you know of and which one do you think it fits into?Slide3
Luminescence Sources
Chemiluminescence
- Light given off by a chemical reaction
Bioluminescence
- Light given off by a chemical reaction within an organismSlide4
Luminescence Sources
Electroluminescence
- Luminescence cause by electric
currents
https://www.youtube.com/watch?v=
BH9LI973H8w
Cathodoluminescence- Electroluminescence cause by electron beamshttps://www.youtube.com/watch?v=qp6tNaUvfNISlide5
Luminescence Sources
Fluorescence
- Luminescence where energy is given off by the movement of
electrons to non-excited state.
Electrons are found in atoms. They can get excited and take in energy. When they release that energy it comes off as
light photons
. Phosphorescence- is a delayed light that is created because electrons are stuck in a high energy state and has not given off the energy as light yet.
https://www.youtube.com/watch?v=
kLEHNYWQl68Slide6
What types of light bulbs do you have in your house?
How often do the light bulbs need changing?
What are some factors that you think about when buying light bulbs? Slide7
Which bulb would you choose?
Incandescent
L.E.D
C.F.L.
Lumens
825
800
900
Wattage
60
11
14
Cost of bulb
6.00 for 12
11.98
4.98 for 2
Life Span
1,000
25,000
10,000
Cost of running the light bulb
over
its life span
$7.872
$36.08
$18.368Slide8
Which bulb would you choose?
Incandescent
L.E.D
C.F.L
Does
it contain mercury
no
no
yes
Can you recycle it?
no
yes
no
Is
it dimmable
yes
yes
noSlide9
http://energy.gov/public-services/homes/saving-electricity/
lighting
http://www.huffingtonpost.com/2014/03/30/daan-roosegaarde_n_5044578.
htmlSlide10
Exit slip
Which light bulb are you likely to buy now that we have compared some? What factors are the most important to you in a light bulb?
Explain in your own words what is the difference between Luminescence and Incandescence light sources.
What is bioluminescence?