The 4th state of matter -Plasma

1. Plasma,Plasma,
the 4the 4
thth
state of matter state of matter
Done by :
Jeremy Teo (14) 1O2

2. What is plasma?What is plasma?
A plasma is a hot ionized gas consisting of
approximately equal numbers of
positively charged ions and negatively
charged electrons.

3. Characteristics of plasmaCharacteristics of plasma
Plasmas are made up of electrically
charged particles, strongly influenced by
electric and magnetic fields.
Neutral gases are not.
Plasmas are considered a distinct "fourth
state of matter."

4. Plasma and geomagnetic fieldsPlasma and geomagnetic fields
Plasma is influenced
◦Externally - by the Earth's magnetic field or
the interplanetary magnetic field and
◦Internally – by the localized charge
concentrations and electric currents that
result from the differential motion of the ions
and electrons.

5. The forces affect the particles within the
plasma. It gives the particles' behaviour a
coherent, collective quality that neutral
gases do not display.

6. The plasma universeThe plasma universe
About 99% of the matter in the
observable universe is in the plasma state,
In our solar system, the Sun, the
interplanetary medium, the
magnetospheres and ionospheres of the
Earth and other planets, as well as the
ionospheres of comets and certain
planetary moons all consist of plasmas.

7. Space plasmasSpace plasmas
The plasmas of interest to space
physicists are extremely tenuous, with
densities dramatically lower than those
achieved in laboratory vacuums.
The temperatures of space plasmas are
very high, ranging from several thousand
degrees Celsius in the plasma sphere to
several million degrees in the ring
current.

8. While the temperatures of the "cooler"
plasmas of the ionosphere and plasma
sphere are typically given in degrees
Kelvin, those of the "hotter"
magnetospheric plasmas are more
commonly expressed in terms of the
average kinetic energies of their
constituent particles measured in
"electron volts."

9. An electron volt (eV) is the energy that
an electron acquires as it is accelerated
through a potential difference of one volt
and is equivalent to 11,600 degrees
Kelvin.
Magnetospheric plasmas are often
characterized as being "cold" or "hot."
Although these labels are quite subjective,
they are widely used in the space physics
literature.

10. As a rule of thumb, plasmas with
temperatures less than about 100 eV are
"cold," while those with temperatures
ranging from 100 eV to 30 keV can be
considered "hot." (Particles with higher
energies--such as those that populate the
radiation belt--are termed "energetic.")

11. Examples of artificially produced Examples of artificially produced
plasmas plasmas
Those found in plasma displays, including
TVs
Inside fluorescent lamps (low energy
lighting), neon signs
Rocket exhaust and ion thrusters
The area in front of a spacecraft's heat
shield during re-entry into
the atmosphere
Inside a corona
discharge ozone generator

12. Plasma ball or plasma globe
Arcs produced by Tesla coils (resonant air
core transformer or disruptor coil that
produces arcs similar to lightning but
with alternating current rather than static
electricity)
Plasmas used in semiconductor device
fabrication including reactive-ion
etching, sputtering, surface
cleaning and plasma-enhanced chemical
vapor deposition
Laser-produced plasmas (LPP), found when
high power lasers interact with materials.

13. Fusion energy research
The electric arc in an arc lamp, an
arc welder or plasma torch
Inductively coupled plasmas (ICP), formed
typically in argon gas for optical
emission spectroscopy or mass
spectrometry
Magnetically induced plasmas (MIP),
typically produced using microwaves as a
resonant coupling method

14. Examples of terrestrial plasmas Examples of terrestrial plasmas
Lightning
Ball lightning
St. Elmo's fire
Upper-atmospheric lightning
The ionosphere
The polar aurorae
Most flames

15. Examples of space and astrophysical Examples of space and astrophysical
plasmasplasmas
The Sun and other stars
(plasmas heated by nuclear fusion)
The solar wind
The interplanetary medium
(space between planets)
The interstellar medium
(space between star systems)

16. The Intergalactic medium
(space between galaxies)
The Io-Jupiter flux tube
Accretion discs
Interstellar nebulae

17. ReferencesReferences
http://pluto.space.swri.edu/IMAGE/glossary/plasma.html
http://www.google.com.sg/
http://www.google.com.sg/imghp?hl=en&tab=wi
http://en.wikipedia.org/wiki/Plasma_(physics)

18. Thank you for all your attention!Thank you for all your attention!