Search results
Results from the WOW.Com Content Network
Continuous charge distribution. The volume charge density ρ is the amount of charge per unit volume (cube), surface charge density σ is amount per unit surface area (circle) with outward unit normal nĚ‚, d is the dipole moment between two point charges, the volume density of these is the polarization density P.
Radio waves can be radiated from an antenna by accelerating electrons in the antenna. This is a coherent process, so the total power radiated is proportional to the square of the number of electrons accelerating. In electrodynamics, the Larmor formula is used to calculate the total power radiated by a nonrelativistic point charge as it accelerates.
A capacitive power supply usually has a rectifier and filter to generate a direct current from the reduced alternating voltage. Such a supply comprises a capacitor, C1 whose reactance limits the current flowing through the rectifier bridge D1. A resistor, R1, connected in series with it protects against voltage spikes during switching operations.
Power Quality Analyzers, often referred to as Power Analyzers, make a digital recording of the voltage and current waveform (typically either one phase or three phase) and accurately calculate true power (watts), apparent power (VA) power factor, AC voltage, AC current, DC voltage, DC current, frequency, IEC61000-3-2/3-12 Harmonic measurement ...
The plotted line represents the variation of instantaneous voltage (or current) with respect to time. This cycle repeats with a frequency that depends on the power system. In electrical engineering, three-phase electric power systems have at least three conductors carrying alternating voltages that are offset in time by one-third of the period ...
Alternatively, the electric potential energy of any given charge or system of charges is termed as the total work done by an external agent in bringing the charge or the system of charges from infinity to the present configuration without undergoing any acceleration.
The formula provides a natural generalization of the Coulomb's law for cases where the source charge is moving: = [′ ′ + ′ (′ ′) + ′] = ′ Here, and are the electric and magnetic fields respectively, is the electric charge, is the vacuum permittivity (electric field constant) and is the speed of light.
Kvar or KVAR may refer to: Kvar, a character from the video game Tales of Symphonia; Kilovolt-amperes reactive, thousand Volt-ampere reactive, a unit of reactive power; KVAR (FM), a radio station (93.7 FM) licensed to Pine Ridge, South Dakota; KPNX, a television station (Channel 12) licensed to Mesa, Arizona, which formerly used the call sign KVAR