When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Volt-ampere - Wikipedia

    en.wikipedia.org/wiki/Volt-ampere

    The volt-ampere (SI symbol: VA, [1] sometimes V⋅A or V A) is the unit of measurement for apparent power in an electrical circuit. It is the product of the root mean square voltage (in volts) and the root mean square current (in amperes). [2] Volt-amperes are usually used for analyzing alternating current (AC) circuits.

  3. Mathematics of three-phase electric power - Wikipedia

    en.wikipedia.org/wiki/Mathematics_of_three-phase...

    Since we have shown that the neutral current is zero we can see that removing the neutral core will have no effect on the circuit, provided the system is balanced. Such connections are generally used only when the load on the three phases is part of the same piece of equipment (for example a three-phase motor), as otherwise switching loads and ...

  4. Ohm's law - Wikipedia

    en.wikipedia.org/wiki/Ohm's_law

    Ohm's law, in the form above, is an extremely useful equation in the field of electrical/electronic engineering because it describes how voltage, current and resistance are interrelated on a "macroscopic" level, that is, commonly, as circuit elements in an electrical circuit.

  5. Kirchhoff's circuit laws - Wikipedia

    en.wikipedia.org/wiki/Kirchhoff's_circuit_laws

    The current entering any junction is equal to the current leaving that junction. i 2 + i 3 = i 1 + i 4. This law, also called Kirchhoff's first law, or Kirchhoff's junction rule, states that, for any node (junction) in an electrical circuit, the sum of currents flowing into that node is equal to the sum of currents flowing out of that node; or equivalently:

  6. Amplifier - Wikipedia

    en.wikipedia.org/wiki/Amplifier

    An operational amplifier is an amplifier circuit which typically has very high open loop gain and differential inputs. Op amps have become very widely used as standardized "gain blocks" in circuits due to their versatility; their gain, bandwidth and other characteristics can be controlled by feedback through an external circuit. Though the term ...

  7. Electric current - Wikipedia

    en.wikipedia.org/wiki/Electric_current

    Current can also be measured without breaking the circuit by detecting the magnetic field associated with the current. Devices, at the circuit level, use various techniques to measure current: Shunt resistors [18] Hall effect current sensor transducers; Transformers (however DC cannot be measured) Magnetoresistive field sensors [19] Rogowski coils

  8. Per-unit system - Wikipedia

    en.wikipedia.org/wiki/Per-unit_system

    In the power systems analysis field of electrical engineering, a per-unit system is the expression of system quantities as fractions of a defined base unit quantity. . Calculations are simplified because quantities expressed as per-unit do not change when they are referred from one side of a transformer to t

  9. Miller theorem - Wikipedia

    en.wikipedia.org/wiki/Miller_theorem

    The op-amp inverting amplifier is a typical circuit, with parallel negative feedback, based on the Miller theorem, where the op-amp differential input impedance is apparently decreased to zero Zeroed impedance uses an inverting (usually op-amp) amplifier with enormously high gain A v → ∞ {\displaystyle A_{v}\to \infty } .