Transcript Solar Energy The Sun as a Star

THE SUN:
Solar Energy
The Sun as a Star
It’s light is the major source of energy for
all planets and life on Earth.
 It’s an “average” star
 4.5 billion years old – ½ way through life
cycle
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http://www.solarviews.com/images/VSS00031.jpg
Sun
Layers
1. Core =
14,500,000 K
2. Radiative Zone =
2,100,000 K
3. Convection Zone =
1,000,000 K
4. Photosphere = 6,000K
5. Chromosphere =
27,000 K
6. Corona =
2,000,000 K
7. Sunspots = 5,000 K
8. Granules
9. Solar Prominence
Sun: A Nuclear Reactor
The Sun does not “burn” like wood.
 The Sun is made of:

78% Hydrogen
 20% Helium
 2% heavier elements
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Because it’s so large, the gravity is very
strong. So, deep inside the temperature
and pressure are very high.
Sun: A Nuclear Reactor (con’t)

Nuclear Fusion: the process where
Hydrogen atoms fuse together to make a
Helium atom (H + H = He) …it’s not that
simple, however..

This is a nuclear
reaction and it
releases energy in
the form of heat and
light.
http://www.ustudy.in/node/3161
Ways Heat Energy can be
Transferred
1.
Conduction: Heat energy transferred by
contact. Energy from a higher energy
atom or molecule gets passed on to one
with less energy when they bump into
each other.
Ways Heat Energy can be
Transferred (con’t)
2. Convection: heat energy transferred by
movement of a liquid or gas. As warm
air gains heat energy, it becomes less
dense and rises. Cooler air sinks.
Ways Heat Energy can be
Transferred (con’t)
3. Radiation: Heat energy transferred
through space.
It’s how Solar energy travels to Earth.
Ways Heat Energy can be
Transferred – all in one!
Draw a
simplified
diagram of
this and label
the types of
heat transfer.
http://blogs.saschina.org/morena0
1pd2016/files/2009/10/ccr.jpg
Solar Energy
Energy comes in many forms, such as
heat and light.
 Solar energy (energy from the Sun) travels
through space as an electromagnetic
wave.

http://www.warrenwilson.edu/~physics/physics2/Formal20
00/sstephens/elecmag.gif
Electromagnetic Radiation

The Sun gives off these types of light in varying amounts. Radio
waves have the longest wavelength & least energy, Gamma Rays
have the shortest wavelength & the most energy. All of these travel
at 300,000 km/sec in space.
http://www.fluxnet-canada.ca/pages/pics/Electromagnetic_spectrum.png
Electromagnetic Radiation
http://asd-www.larc.nasa.gov/erbe/components2.gif
Solar Energy =
Electromagnetic Radiation
The 2 main types of solar radiation
(aka Electromagnet radiation) are heat
(aka infrared rays) and light (aka visible
light).
 The Sun also gives off some UV light (7%)
and a tiny amount of radio waves,
microwaves, X-rays, Gamma rays.
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