Search results
Results From The WOW.Com Content Network
Radio propagation is the behavior of radio waves as they travel, or are propagated, from one point to another in vacuum, or into various parts of the atmosphere. [1]: 26‑1 As a form of electromagnetic radiation, like light waves, radio waves are affected by the phenomena of reflection, refraction, diffraction, absorption, polarization, and scattering. [2]
Flight-time equivalent dose (FED) is an informal unit of measurement of ionizing radiation exposure. Expressed in units of flight-time (i.e., flight-seconds, flight-minutes, flight-hours), one unit of flight-time is approximately equivalent to the radiological dose received during the same unit of time spent in an airliner at cruising altitude.
One hour after a surface burst, the radiation from fallout in the crater region is 30 grays per hour (Gy/h). [clarification needed] Civilian dose rates in peacetime range from 30 to 100 μGy per year. For yields of up to 10 kt, prompt radiation is the dominant producer of casualties on the battlefield. Humans receiving an acute incapacitating ...
Since the nature of such interactions is statistical, the number of collisions required to bring a radiation particle to rest within the medium will vary slightly with each particle (i.e., some may travel further and undergo fewer collisions than others). Hence, there will be a small variation in the range, known as straggling.
Penetration depth is a measure of how deep light or any electromagnetic radiation can penetrate into a material. It is defined as the depth at which the intensity of the radiation inside the material falls to 1/e (about 37%) of its original value at (or more properly, just beneath) the surface.
Electromagnetic radiation phenomena with wavelengths ranging from one meter to one millimeter are called microwaves; with frequencies between 300 MHz (0.3 GHz) and 300 GHz. At radio and microwave frequencies, EMR interacts with matter largely as a bulk collection of charges which are spread out over large numbers of affected atoms.
Neutron transport (also known as neutronics) is the study of the motions and interactions of neutrons with materials. Nuclear scientists and engineers often need to know where neutrons are in an apparatus, in what direction they are going, and how quickly they are moving.
Radiative transfer (also called radiation transport) is the physical phenomenon of energy transfer in the form of electromagnetic radiation. The propagation of radiation through a medium is affected by absorption , emission , and scattering processes.