Sources of EM Radiation

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Sources of EM Radiation
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zetaherz
picometer
exahertz
nanometer
petahertz
micrometer
terahertz
millimeter
gigahertz
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Dish-type antennas, varying in diameter from 8 to
30 m, serving an Earth station in a satellite
communications network.
Aercibo Observatory Radio Telescope 305 m
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Vibrating charges and EM wave
Oscillating dipole
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Electron transitions in the Bohr model of the
Hydrogen atom
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Neon lights and other discharge lamps
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OR
wavelength of 555 nanometres has a frequency of
540 THz (540  1012 Hz). Each photon has an
energy E of h?  3.58  10-19 J.
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Types of Spectra
Emission
Absorption
Continuous
Line
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The Visible Spectrum
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Black body radiation
Blackbody radiation and stellar luminosity
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The wavelength of radiation produced by an object
is related to its temperature
m.K
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Powering the Sunproton proton chain
reactionSuns core
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Different wavelengths of light penetrate the
Earth's atmosphere to different depths
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The reason why the sea is blue!
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X - rays
The Sun also emits X-rays - here is what the Sun
looked like in X-rays on April 27th, 2000. This
image was taken by the Yokoh satellite
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UV
Image of the Sun taken at an Extreme Ultraviolet
wavelength - 171 Å. This image was taken by a
satellite named SOHO and it shows what the Sun
looked like on April 24, 2000.
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Gamma ray bursts (GRBs) are the most luminous
electromagnetic events occurring in the universe!
Gamma-ray bursts can release more energy in 10 s
than the Sun will emit in its entire 10
billion-year lifetime! So far, it appears that
all of the bursts we have observed have come from
outside the Milky Way Galaxy.
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Lightning animation
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Bioluminescence
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Glowing bio-engineered tobacco plant
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Imaging of Ultraweak Spontaneous Photon
Emission from Human Body Displaying Diurnal
Rhythm Masaki Kobayashi1, Daisuke Kikuchi1,
Hitoshi Okamura2,3 1 Department of Electronics
and Intelligent Systems, Tohoku Institute of
Technology, Sendai, Japan, 2 Department of
Systems Biology, Kyoto University Graduate School
of Pharmaceutical Sciences, Kyoto, Japan, 3
Department of Brain Science, Kobe University
Graduate School of Medicine, Kobe, Japan PLoS one
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Drowning in a sea of EM radiation
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Supercuster of distant galaxies
Sun
Redshift of spectral lines in the optical spectrum