News tagged with electromagnetic radiation
Study resolves century-long debate over how to describe electromagnetic momentum density in matter
(PhysOrg.com) -- Researchers from the NIST Center for Nanoscale Science and Technology and the University of British Columbia have shown that the interaction between a light pulse and a light-absorbing object, including the ...
Dec 29, 2011 |
4.4 / 5 (14) |
23
|
New electromechanical circuit sets record beating microscopic 'drum'
Described in the March 10 issue of Nature, the NIST experiments created strong interactions between microwave light oscillating 7.5 billion times per second and a "micro drum" vibrating at radio frequencies 11 mil ...
Mar 09, 2011 |
5 / 5 (2) |
0
|
A breakthrough for terahertz semiconductor lasers
(PhysOrg.com) -- Potential applications, says an engineering professor, include disease diagnosis and detection of concealed explosives.
Jan 13, 2011 |
3.5 / 5 (11) |
3
|
'Necropanspermia' suggested as a way of seeding life on Earth
(PhysOrg.com) -- Panspermia is a mechanism for spreading organic material throughout the galaxy, but the destructive effects of cosmic rays and ultraviolet light tend to mean most organisms would be destroyed ...
Forcing mismatched elements together could yield better solar cells
(PhysOrg.com) -- In what could be a step toward higher efficiency solar cells, an international team including University of Michigan professors has invalidated the most commonly used model to explain the behavior of a unique ...
Sep 08, 2010 |
4.8 / 5 (12) |
3
|
Variations in fine-structure constant suggest laws of physics not the same everywhere
(PhysOrg.com) -- One of the most controversial questions in cosmology is why the fundamental constants of nature seem fine-tuned for life. One of these fundamental constants is the fine-structure constant, ...
Radio Waves: Alternative Power Source
(PhysOrg.com) -- Researchers at Duke University are harvesting ambient radio waves to power small microprocessor devices that consume very little energy. Devices such as sensors that monitor critical environmental ...
Probing the dark side of the universe
Advancing into the next frontier in astrophysics and cosmology depends on our ability to detect the presence of a particular type of wave in space, a primordial gravitational wave. Much like ripples moving ...
May 20, 2010 |
4.6 / 5 (15) |
99
|
New 'metamaterial' device may lead to see-through cameras and scanners
Devices that can mimic Superman's X-ray vision and see through clothing, walls or human flesh are the stuff of comic book fantasy, but a group of scientists at Boston University (BU) has taken a step toward making such futuristic ...
May 06, 2010 |
4.9 / 5 (12) |
1
|
Scientists reveal how snakes 'see' at night
Scientists revealed Sunday for the first time how some snakes can detect the faint body heat exuded by a mouse a metre (three feet) away with enough precision and speed to hunt in the dark.
Mar 15, 2010 |
4.4 / 5 (7) |
0
Gamma-ray photon race ends in dead heat; Einstein wins this round
Racing across the universe for the last 7.3 billion years, two gamma-ray photons arrived at NASA's orbiting Fermi Gamma-ray Space Telescope within nine-tenths of a second of one another. The dead-heat finish ...
Oct 28, 2009 |
4.6 / 5 (37) |
62
Very High Energy Gamma Rays
(PhysOrg.com) -- Gamma-rays are the most energetic known form of electromagnetic radiation, with each gamma ray being at least one hundred thousand times more energetic than an optical light photon. The most ...
Sep 25, 2009 |
4.6 / 5 (13) |
3
A Theory of Dark Matter
Among the most astounding, unexpected, and important achievements of the past century (or even more) have been the discoveries of dark matter and dark energy, collectively dubbed the "dark sector."
Sep 08, 2009 |
3.6 / 5 (45) |
58
Testing relativity in the lab
Even Albert Einstein might have been impressed. His theory of general relativity, which describes how the gravity of a massive object, such as a star, can curve space and time, has been successfully used to ...
Jul 20, 2009 |
4.7 / 5 (14) |
25
High-energy Electrons Could Come from Pulsars -- or Dark Matter
(PhysOrg.com) -- Something in our galactic neighborhood seems to be producing large numbers of high-energy electrons, according to new data gathered by the Fermi Gamma-ray Space Telescope. The electrons could ...
May 05, 2009 |
4.2 / 5 (9) |
1
Electromagnetic radiation
Electromagnetic radiation (sometimes abbreviated EMR) is a ubiquitous phenomenon that takes the form of self-propagating waves in a vacuum or in matter. It consists of electric and magnetic field components which oscillate in phase perpendicular to each other and perpendicular to the direction of energy propagation. Electromagnetic radiation is classified into several types according to the frequency of its wave; these types include (in order of increasing frequency and decreasing wavelength): radio waves, microwaves, terahertz radiation, infrared radiation, visible light, ultraviolet radiation, X-rays and gamma rays. A small and somewhat variable window of frequencies is sensed by the eyes of various organisms; this is what we call the visible spectrum, or light.
EM radiation carries energy and momentum that may be imparted to matter with which it interacts.
For more information about Electromagnetic radiation, read the full article at
Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.