Electromagnetic radiation
... microscopic motions within the matter, coming tothermal equilibrium and manifesting itself as thermal energy in the material. With a few exceptions such as fluorescence, harmonic generation,photochemical reactions and the photovoltaic effect, absorbed electromagnetic radiation simply deposits its en ...
... microscopic motions within the matter, coming tothermal equilibrium and manifesting itself as thermal energy in the material. With a few exceptions such as fluorescence, harmonic generation,photochemical reactions and the photovoltaic effect, absorbed electromagnetic radiation simply deposits its en ...
atoms - Waterford Public Schools
... In a given compound, the relative numbs and kinds of atoms are constant Based on In chemical reactions, the total mass of materials present before and after is the same ...
... In a given compound, the relative numbs and kinds of atoms are constant Based on In chemical reactions, the total mass of materials present before and after is the same ...
ASRC Aerospace Corporation Final Report
... exploding stars. GCR is also isotropic since the particle origins are distributed approximately uniformly over space. The composition tends toward higheratomic-mass ions, maxing out at fully ionized iron. The GCR spectrum begins an energy cutoff at approximately 1,000 MeV, where lower-intensity-part ...
... exploding stars. GCR is also isotropic since the particle origins are distributed approximately uniformly over space. The composition tends toward higheratomic-mass ions, maxing out at fully ionized iron. The GCR spectrum begins an energy cutoff at approximately 1,000 MeV, where lower-intensity-part ...
Electromagnetic Waves
... all waves travel at the same speed in a vacuum, like space, EMW travel at 300,000 km per second When EMW travel through our atmosphere, they travel more slowly but they are still the fastest waves Takes 8 minutes for sunlight to reach earth! ...
... all waves travel at the same speed in a vacuum, like space, EMW travel at 300,000 km per second When EMW travel through our atmosphere, they travel more slowly but they are still the fastest waves Takes 8 minutes for sunlight to reach earth! ...
transparencies - Indico
... Astronomers don't know precisely where all these particles come from. The sun is a known source of cosmic rays which are produced by high energy explosions (solar flares) in the sun's atmosphere, but the amount of cosmic rays emitted by the sun is too low to account for all the cosmic rays which str ...
... Astronomers don't know precisely where all these particles come from. The sun is a known source of cosmic rays which are produced by high energy explosions (solar flares) in the sun's atmosphere, but the amount of cosmic rays emitted by the sun is too low to account for all the cosmic rays which str ...
ATOMIC PHYSICS
... a) laws of photoemission (based on experiments) 1. The number of photoelectrons emitted per second depends on the intensity of incident radiation (number of quanta incident – discovered later) 2. Speed of photoelectrons varies from zero to v max , which depends on the frequency of the incident radia ...
... a) laws of photoemission (based on experiments) 1. The number of photoelectrons emitted per second depends on the intensity of incident radiation (number of quanta incident – discovered later) 2. Speed of photoelectrons varies from zero to v max , which depends on the frequency of the incident radia ...
Atomic Structure Development
... α rays – +ve charge stopped by a piece of paper; β rays – -ve charge stopped by metal foil; γ rays – no charge , high energy required several cm of lead to stop them. Concluded - radioactive elements transmutated from one element to another. Introduced half-life, number of decaying atoms ∝ total no ...
... α rays – +ve charge stopped by a piece of paper; β rays – -ve charge stopped by metal foil; γ rays – no charge , high energy required several cm of lead to stop them. Concluded - radioactive elements transmutated from one element to another. Introduced half-life, number of decaying atoms ∝ total no ...
Week 13 - Electromagnetic Waves
... they start to oscillate, i.e. they produce a current. For the charges to be able to move significantly they must have some space to move on. Therefore the vertical antennas indicate that the electromagnetic waves are vertically polarized so the electric field in the wave is able to do work on those ...
... they start to oscillate, i.e. they produce a current. For the charges to be able to move significantly they must have some space to move on. Therefore the vertical antennas indicate that the electromagnetic waves are vertically polarized so the electric field in the wave is able to do work on those ...
Joseph John Thomson 1856-1940
... and sealing wax laboratory" into the world's preeminent center for experimental nuclear physics. It has been said that Thomson, like Michael Faraday, was greater than his discoveries. However, those discoveries were far from insignificant. Thomson and his student Ernest Rutherford were the first to ...
... and sealing wax laboratory" into the world's preeminent center for experimental nuclear physics. It has been said that Thomson, like Michael Faraday, was greater than his discoveries. However, those discoveries were far from insignificant. Thomson and his student Ernest Rutherford were the first to ...
principles1.bak - UCL Department of Geography
... • Provide basis for understanding type of information that can be (usefully) retrieved via Earth observation (EO) • Why we choose given regions of the EM spectrum in which to make measurements ...
... • Provide basis for understanding type of information that can be (usefully) retrieved via Earth observation (EO) • Why we choose given regions of the EM spectrum in which to make measurements ...
principles1 - UCL Department of Geography
... • Provide basis for understanding type of information that can be (usefully) retrieved via Earth observation (EO) • Why we choose given regions of the EM spectrum in which to make measurements ...
... • Provide basis for understanding type of information that can be (usefully) retrieved via Earth observation (EO) • Why we choose given regions of the EM spectrum in which to make measurements ...
Absorbance of Electromagnetic Radiation
... • The measurement of this attenuation, which we call absorbance, • The energy levels have well-defined values (i.e., they are quantized). • Absorption only occurs when the photon's energy matches the difference in energy, E, between two energy levels. • A plot of absorbance as a function of the pho ...
... • The measurement of this attenuation, which we call absorbance, • The energy levels have well-defined values (i.e., they are quantized). • Absorption only occurs when the photon's energy matches the difference in energy, E, between two energy levels. • A plot of absorbance as a function of the pho ...
Radiation
In physics, radiation is the emission or transmission of energy in the form of waves or particles through space or through a material medium. This includes: electro-magnetic radiation (also known as ""continuum radiation"") γ such as radio waves, visible light, and x-rays particle radiation such as α, β, and neutron radiation (discrete energy per particle) acoustic radiation such as ultrasound, sound, and seismic waves. (dependent on intervening mass for transmission)Radiation is often categorized as either ionizing or non-ionizing depending on the energy of the radiated particles. Ionizing radiation carries more than 10 eV, which is enough to ionize atoms and molecules, and break chemical bonds. This is an important distinction due to the large difference in harmfulness to living organisms. A common source of ionizing radiation is radioactive materials that emit α, β, or γ radiation, consisting of helium nuclei, electrons or positrons, and photons, respectively. Other sources include X-rays from medical radiography examinations and muons, mesons, positrons, neutrons and other particles that constitute the secondary cosmic rays that are produced after primary cosmic rays interact with Earth's atmosphere.Gamma rays, X-rays and the higher energy range of ultraviolet light constitute the ionizing part of the electromagnetic spectrum. The lower-energy, longer-wavelength part of the spectrum including visible light, infrared light, microwaves, and radio waves is non-ionizing; its main effect when interacting with tissue is heating. This type of radiation only damages cells if the intensity is high enough to cause excessive heating. Ultraviolet radiation has some features of both ionizing and non-ionizing radiation. While the part of the ultraviolet spectrum that penetrates the Earth's atmosphere is non-ionizing, this radiation does far more damage to many molecules in biological systems than can be accounted for by heating effects, sunburn being a well-known example. These properties derive from ultraviolet's power to alter chemical bonds, even without having quite enough energy to ionize atoms.The word radiation arises from the phenomenon of waves radiating (i.e., traveling outward in all directions) from a source. This aspect leads to a system of measurements and physical units that are applicable to all types of radiation. Because such radiation expands as it passes through space, and as its energy is conserved (in vacuum), the intensity of all types of radiation from a point source follows an inverse-square law in relation to the distance from its source. This law does not apply close to an extended source of radiation or for focused beams.