Download Nuclear Fusion

In the past, and in many countries
even today, phenomena such as
solar eclipses have been cause for
great fear, because they represent a
break in that familiar pattern, cutting
off the light from the sun for awhile,
and who could be sure if the sun
would ever come back?
Light
The form of radiant energy that stimulates the organs of
sight. Visible light is only a small part of the
electromagnetic spectrum.
Radio Waves
– Microwaves
– Infrared
– Visible
– Ultraviolet
– x-rays
– Gamma Rays
What is a photon
word photo (meaning "light")
► The quantum unit of electromagnetic
energy was called a "photon
► Greek
Light acts as a WAVE
► The
frequency of the electromagnetic
wave can be varied over the entire
positive range, but cannot be reduced
to zero.
► The
energy in the wave is continuously
variable, with a minimum energy of
any non-zero value, and no maximum
value.
Light as a PARTICLE
►A
single photon has a fixed, discrete energy level.
► Each color of light has its own unique energy level.
► The intensity of visible light can be increased or
decreased only by changing the number of
photons present.
► The same rules hold true for electromagnetic
spectrum outside the visible range.
► In
1905, Albert Einstein worked out the
primary equation involved. These
experiments confirmed the conclusion that
light is not a continuously wave-like
phenomenon, but rather involves particlelike "corpuscles" of energy, now called
photons, which are the quanta of
electromagnetic energy.
Photoelectric Effect
► Light
falling on metal can cause electrons to
be ejected.
► Light
color not intensity determines if
electrons are freed from a metallic surface or
not.
► Kinetic
Energy of ejected electrons does
depend on the color of the light (ie the
frequency of incident light)
► Light
intensity increases # of electrons freed
but not their energy.
►E
►E
=hf
= energy of the photon
h = Planck's Constant 6.626x10-34J.s
f = The frequency of the wave
Photoelctric effect applet
►
http://www.ifae.es/xec/phot2.html
Atomic Energy E = m c
► The
2
ancient Greeks said the smallest
part of nature is an atom. But they did
not know 2,000 years ago about
nature's even smaller parts.
Nuclear Fission
► Fission
means to split apart
► An atom's nucleus can be split apart. When
this is done, a tremendous amount of
energy is released.
► The energy is both heat and light energy.
► Einstein said that a very small amount of
matter contains a very LARGE amount of
energy.
► This
energy, when let out slowly, can be
harnessed to generate electricity.
► Inside the reactor of an atomic power plant,
uranium atoms are split apart in a controlled
chain reaction.
Pros & Cons
► Nuclear
Fission Pros
 A lot of energy from a little bit of material
► Nuclear
Fission Cons
 Radioactive waste products
Nuclear Fusion
► Fusion
means joining smaller nuclei (the
plural of nucleus) to make a larger nucleus.
► The sun uses nuclear fusion of hydrogen
atoms into helium atoms. This gives off heat
and light and other radiation
Pros & Cons
► Nuclear
Fusion Pros
 creates less radioactive material than fission,
 supply of fuel can last longer than the sun.
► Nuclear
Fusion Cons
 Currently takes more energy than is gotten out
 trouble learning how to control the reaction in a
contained space.