Portal:Electronics

Thomas Alva Edison (February 11, 1847 – October 18, 1931) was an American inventor and businessman who developed many devices which greatly influenced life worldwide into the 21st century. He was one of the first inventors to apply the principles of mass production to the process of invention, and can therefore be credited with the creation of the first industrial research laboratory. Edison is considered one of the most prolific inventors in history, holding 1,097 U.S. patents, as well as many patents in the United Kingdom, France, and Germany.

In physics, Coulomb's law is an inverse-square law indicating the magnitude and direction of electrostatic force that one stationary, electrically charged object of small dimensions exerts on another. It is named after Charles-Augustin de Coulomb who used a torsion balance to establish it.

The magnitude of the electrostatic force between two point charges is directly proportional to the magnitudes of each charge and inversely proportional to the square of the distance between the charges.

For calculating the direction and magnitude of the force simultaneously, one will wish to consult the full vector version of the Law

${\displaystyle {\vec {F}}={\frac {1}{4\pi \epsilon _{0}}}{\frac {q_{1}q_{2}}{|{\vec {r}}|^{3}}}{\vec {r}}={\frac {1}{4\pi \epsilon _{0}}}{\frac {q_{1}q_{2}}{|{\vec {r}}|^{2}}}{\hat {r}}}$

where ${\displaystyle {\vec {F}}}$ is the electrostatic force vector, ${\displaystyle q_{1}}$ is the charge on which the force acts, ${\displaystyle q_{2}}$ is the acting charge, ${\displaystyle {\vec {r}}={\vec {r_{1}}}-{\vec {r_{2}}}}$ is the distance vector between the two charges, ${\displaystyle {\vec {r_{1}}}\ }$ is position vector of ${\displaystyle q_{1}}$, ${\displaystyle {\vec {r_{2}}}\ }$ is position vector of ${\displaystyle q_{2}}$, ${\displaystyle {\hat {r}}}$ is a unit vector pointing in the direction of ${\displaystyle {\vec {r}}}$, and ${\displaystyle \epsilon _{0}}$ is a constant called the permittivity of free space.

This vector equation indicates that opposite charges attract, and like charges repel. When ${\displaystyle q_{1}q_{2}\ }$ is negative, the force is attractive. When positive, the force is repulsive.

• ... that despite Daniel Lopatin's electronic album Chuck Person's Eccojams Vol. 1 having a limited 2010 release on cassette tapes, it became a foundational album for the vaporwave genre?
• ... that in Yugoslavia, Rudi Čajavec, the electronics company that produced various components of the M-84 tank, also made guitar amplifiers?
• ... that a 1982 court case established that video games may qualify for multiple types of U.S. copyright protection?
• ... that in 2017 the British travel magazine Wanderlust rated Azerbaijan's electronic visa as the easiest visa to obtain in the world?
• ... that Last Call BBS contains a chip-manufacturing game, a model-building simulator, a game of solitaire, and more?
• ... that in 2019, Chinese electronics company Xiaomi posted a video of their third-quarterly financial report featuring a parody of the anime song "Renai Circulation"?

A scanner is a radio receiver that automatically tunes, or scans, two or more discrete frequencies. Generally, scanners cover the non-broadcast radio bands between 30 and 950 MHz using FM. Popular amongst hobbyists, reporters, corporate spies, criminals and lawyers, scanners allow chosen frequencies to be stored in memory banks to allow them to be monitored later and will only stop scanning when there is a signal strong enough to break the radio's squelch setting.