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  2. Electric current - Wikipedia

    en.wikipedia.org/wiki/Electric_current

    When oscillating electric currents flow at the correct voltages within radio antennas, radio waves are generated. In electronics, other forms of electric current include the flow of electrons through resistors or through the vacuum in a vacuum tube, the flow of ions inside a battery, and the flow of holes within metals and semiconductors.

  3. Skin effect - Wikipedia

    en.wikipedia.org/wiki/Skin_effect

    The electric current flows mainly at the skin of the conductor, between the outer surface and a level called the skin depth. Skin depth depends on the frequency of the alternating current; as frequency increases, current flow becomes more concentrated near the surface, resulting in less skin depth.

  4. Speed of electricity - Wikipedia

    en.wikipedia.org/wiki/Speed_of_electricity

    Without the presence of an electric field, the electrons have no net velocity. When a DC voltage is applied, the electron drift velocity will increase in speed proportionally to the strength of the electric field. The drift velocity in a 2 mm diameter copper wire in 1 ampere current is approximately 8 cm per hour. AC voltages cause no net movement.

  5. Faraday's law of induction - Wikipedia

    en.wikipedia.org/wiki/Faraday's_law_of_induction

    Alternating electric current flows through the solenoid on the left, producing a changing magnetic field. This field causes, by electromagnetic induction, an electric current to flow in the wire loop on the right. The most widespread version of Faraday's law states:

  6. Direct current - Wikipedia

    en.wikipedia.org/wiki/Direct_current

    Direct current (DC) is one-directional flow of electric charge. An electrochemical cell is a prime example of DC power. Direct current may flow through a conductor such as a wire, but can also flow through semiconductors , insulators , or even through a vacuum as in electron or ion beams .

  7. Electromagnetic induction - Wikipedia

    en.wikipedia.org/wiki/Electromagnetic_induction

    This field causes, by electromagnetic induction, an electric current to flow in the wire loop on the right. Electromagnetic or magnetic induction is the production of an electromotive force (emf) across an electrical conductor in a changing magnetic field .

  8. Alternating current - Wikipedia

    en.wikipedia.org/wiki/Alternating_current

    A schematic representation of long distance electric power transmission. From left to right: G=generator, U=step-up transformer, V=voltage at beginning of transmission line, Pt=power entering transmission line, I=current in wires, R=total resistance in wires, Pw=power lost in transmission line, Pe=power reaching the end of the transmission line, D=step-down transformer, C=consumers.

  9. Ohm's law - Wikipedia

    en.wikipedia.org/wiki/Ohm's_law

    Similarly, the rate of flow of electrical charge, that is, the electric current, through an electrical resistor is proportional to the difference in voltage measured across the resistor. More generally, the hydraulic head may be taken as the analog of voltage, and Ohm's law is then analogous to Darcy's law which relates hydraulic head to the ...