Liénard–Wiechert potential 1970-01-01
The Liénard–Wiechert potential is a solution to the equations of electrodynamics that describes the electromagnetic field generated by a moving point charge. It is particularly important in the context of special relativity, as it incorporates the effects of the charge's motion, allowing for the calculation of electric and magnetic fields produced by a charged particle moving with arbitrary velocity.
Longitudinal-section mode 1970-01-01
The term "longitudinal-section mode" is typically used in various fields like biology, anatomy, engineering, and occasionally in imaging technologies (such as MRI or ultrasound). Here’s a general understanding of what this mode represents in a few contexts: 1. **Anatomy and Biology**: In anatomical studies, a longitudinal section refers to a cutting technique that divides a specimen along its longest dimension. This is often used to examine the internal structures of organs or organisms.
MODTRAN 1970-01-01
MODTRAN, which stands for MODerate Resolution TRANsmission, is a computer program developed to model the transmission of electromagnetic radiation through the Earth's atmosphere. It is commonly used in atmospheric science, remote sensing, and environmental studies to simulate how light interacts with atmospheric gases, aerosols, and clouds. MODTRAN is particularly focused on the infrared, visible, and ultraviolet portions of the electromagnetic spectrum.
Mathematical descriptions of opacity 1970-01-01
Opacity, in a mathematical context, often refers to the measure of how impenetrable a medium is to electromagnetic radiation, such as light. This concept is important in various fields such as astrophysics, materials science, and computer graphics. Below are some mathematical frameworks and concepts used to describe opacity: ### 1. **Attenuation Coefficient** The attenuation of light as it passes through a medium can be described using an exponential decay model.
Meta-waveguide 1970-01-01
A meta-waveguide is an advanced optical or electromagnetic waveguide that utilizes metamaterials or engineered structures to control the propagation of waves, such as light or radio waves, in innovative ways. Unlike conventional waveguides that rely on standard materials and geometries, meta-waveguides leverage the unique properties of metamaterials, which can exhibit unusual behaviors not found in natural materials, such as negative refractive index, extreme anisotropy, or bandgap effects.
Microwave transmission 1970-01-01
Microwave transmission is a form of communication that uses microwave frequencies, typically in the range of 1 GHz to 300 GHz, to transmit information wirelessly over long distances. This technology is often used for telecommunications, including television broadcasting, internet services, and mobile communications. ### Key Aspects of Microwave Transmission: 1. **Frequency Bands**: Microwave transmission falls within specific frequency bands, including L-band, S-band, C-band, X-band, Ku-band, Ka-band, and others.
Mode (electromagnetism) 1970-01-01
In the context of electromagnetism, "mode" typically refers to a specific pattern of electromagnetic field distribution in a given physical structure, such as waveguides, cavities, or resonators. Modes are associated with the solutions to Maxwell's equations under certain boundary conditions, and they can be characterized by their frequency and spatial field distributions.
Multipolarity of gamma radiation 1970-01-01
Multipolarity in the context of gamma radiation refers to the different angular momentum states associated with the emission of gamma rays from an excited nucleus. When a nucleus transitions from a higher energy state to a lower one, it can emit gamma radiation, which can be classified based on the multipolarity of the emitted radiation.
Multipole radiation 1970-01-01
Multipole radiation refers to the electromagnetic radiation emitted by a system that can be described by the multipole expansion of its electric or magnetic fields. In classical electrodynamics, charge distributions and currents can be represented by a series of terms that describe their contributions to the electromagnetic field, grouped by their symmetry and decay behavior with distance from the source.
Non-ionizing radiation 1970-01-01
Non-ionizing radiation refers to a type of electromagnetic radiation that does not carry enough energy to ionize atoms or molecules, meaning it cannot remove tightly bound electrons from their orbits around atoms. As a result, non-ionizing radiation generally poses a lower risk for biological damage compared to ionizing radiation, which includes X-rays and gamma rays. Non-ionizing radiation includes a range of electromagnetic frequencies, such as: 1. **Radio Waves**: Used for communication (e.g.
Nuclear electromagnetic pulse 1970-01-01
A Nuclear Electromagnetic Pulse (NEMP) is a burst of electromagnetic energy generated by a nuclear explosion. This phenomenon occurs due to the interaction of gamma rays emitted during the explosion with the Earth's atmosphere and magnetic field, leading to the production of high-energy electrons. These electrons, in turn, create a powerful electromagnetic pulse. NEMP is characterized by its ability to disrupt or damage electrical and electronic systems over a wide area.
Opacity (optics) 1970-01-01
In optics, opacity refers to the property of a material that prevents light from passing through it. An opaque material does not allow any light transmission, making it impossible to see through. This is in contrast to transparent materials, which allow most light to pass, and translucent materials, which allow some light to pass but scatter it in different directions. Opacity is typically measured in terms of the percentage of light that is absorbed or reflected by a material versus the percentage that is transmitted.
Operation Fishbowl 1970-01-01
Operation Fishbowl was a series of high-altitude nuclear tests conducted by the United States in 1962 as part of the broader Project Dominic. The tests aimed to investigate the effects of nuclear explosions in the upper atmosphere, particularly concerning electromagnetic pulses (EMPs) and related phenomena.
Optical radiation 1970-01-01
Optical radiation refers to the portion of the electromagnetic spectrum that is visible to the human eye, as well as the radiation just outside the visible range. It encompasses wavelengths from approximately 100 nanometers (nm) to 1 millimeter (mm), which includes: 1. **Ultraviolet (UV) Radiation**: Wavelengths from about 100 nm to 400 nm. UV radiation is primarily associated with sun exposure and can affect the skin and eyes.
Optics 1970-01-01
Optics is the branch of physics that focuses on the study of light and its interactions with matter. It encompasses the behavior of light in various mediums, including reflection, refraction, diffraction, and polarization. There are two main branches of optics: 1. **Geometric Optics**: This branch deals with the approximation of light as rays. It studies how light travels in straight lines, how it interacts with lenses and mirrors, and how images are formed by optical systems.
Penetration depth 1970-01-01
Penetration depth is a term used in various scientific and engineering contexts, primarily in fields like physics, materials science, and geophysics. It generally refers to the distance that a particular object or wave can penetrate into a medium before its intensity or effect diminishes significantly.
Personal RF safety monitor 1970-01-01
A Personal RF Safety Monitor is a device designed to measure and monitor radiofrequency (RF) radiation exposure in real-time. These devices are particularly important for individuals who work in environments where they are exposed to RF emissions, such as telecommunications, broadcasting, and various industrial applications. The primary functions of a Personal RF Safety Monitor include: 1. **Real-Time Monitoring**: It continuously measures RF radiation levels and provides instant feedback to the user about their exposure levels.
Photometry (astronomy) 1970-01-01
Photometry in astronomy is the study and measurement of the intensity and brightness of light from celestial objects. It involves quantifying the amount of light received from stars, galaxies, and other astronomical sources across various wavelengths, primarily in the visible spectrum, but also in ultraviolet and infrared ranges. Key aspects of photometry in astronomy include: 1. **Measurement of Brightness**: Photometry provides a way to measure the apparent magnitudes of celestial objects, which quantifies how bright they appear from Earth.
Plane of polarization 1970-01-01
The plane of polarization refers to the orientation of the electric field vector of a light wave in a plane perpendicular to the direction of propagation of the wave. Light is an electromagnetic wave, and it consists of oscillating electric and magnetic fields. In unpolarized light, the electric field oscillates in multiple directions perpendicular to the direction of travel. However, in polarized light, the electric field oscillates in a specific direction.
Polarization (physics) 1970-01-01
In physics, polarization refers to the orientation of the oscillations of a wave, particularly electromagnetic waves such as light. When light waves are produced, they typically oscillate in multiple planes; however, polarization restricts these oscillations to a single plane. There are several key concepts related to polarization: 1. **Types of Polarization**: - **Linear Polarization**: The electric field of the light wave oscillates in a single plane.