Flux

Flux is a simple and ubiquitous concept throughout physics and applied mathematics describing the flow of a physical property in space, frequently also with time variation. It is the basis of the field concept in physics and mathematics. There exist two common usages of the term flux, each with rigorous mathematical frameworks: For transport phenomena, flux is defined as a vector, whereas in electromagnetism, flux is a scalar quantity, as defined by the surface integral. The terms "flux", "current", "flux density", "current density", can sometimes be used interchangeably and ambiguously, though the terms used below match those of the contexts in the literature.

Origin of the term

The word flux comes from Latin: fluxus means "flow", and fluere is "to flow". As fluxion, this term was introduced into differential calculus by Isaac Newton.

Flux as flow rate per unit area

In transport phenomena (heat transfer, mass transfer and fluid dynamics), flux is defined as the rate of flow of a property per unit area, which has the dimensions [quantity]·[time]⁻¹·[area]⁻¹. For example, the magnitude of a river's current, i.e. the amount of water that flows through a cross-section of the river each second, or the amount of sunlight that lands on a patch of ground each second is also a kind of flux.

Flux Pavilion

Joshua Steele, better known by his stage name Flux Pavilion, is an English dance music record producer, singer-songwriter, DJ and label owner who has been performing since 2008.

Flux Pavilion has headlined three US tours, two UK tours, and several festival DJ sets, including Glastonbury, Reading, Coachella, and EDC Vegas. He has also made live performances with Example, Foreign Beggars and Chiddy Bang. Flux has listed his sound to be inspired by The Prodigy and Rusko.

Career

Flux Pavilion co-founded Circus Records along with childhood friend Doctor P, in 2009 with the backing of D&B pioneer DJ Swan-E and Earl Falconer of UB40.

In 2011 he produced the single "Bass Cannon", which peaked at number 56 on the UK Singles Chart, and was placed on the Radio 1 A-List. Along with Doctor P, Flux Pavilion presented the 2011 compilation album Circus One, to which he contributed four tracks. He is arguably best known for his song "I Can't Stop" from the Lines in Wax EP. In February 2011, Chiddy Bang created a freestyle to the song, which has appeared on their Peanut Butter and Swelly mixtape. In August 2011, the track was sampled by producer Shama "Sak Pase" Joseph for the song "Who Gon Stop Me" by Jay-Z and Kanye West on their collaborative album Watch the Throne. On 5 March 2012, "I Can't Stop" was used in the viral Kony 2012 campaign. It was also featured in the 2012 video game SSX, the 2013 film The Great Gatsby and the trailer for Ron Howard's 2013 film Rush starring Chris Hemsworth.

Khan Academy

Khan Academy is a non-profit educational organization created in 2006 by educator Salman Khan with the aim of providing a free, world-class education for anyone, anywhere. The organization produces short lectures in the form of YouTube videos. In addition to micro lectures, the organization's website features practice exercises and tools for educators. All resources are available for free to anyone around the world. The main language of the website is English, but the content is also available in other languages.

History

The founder of the organization, Salman Khan, was born in New Orleans, Louisiana, United States to immigrant parents from Bangladesh and India. After earning three degrees from the Massachusetts Institute of Technology (a BS in mathematics, a BS in electrical engineering and computer science, and an MEng in electrical engineering and computer science), he pursued an MBA from Harvard Business School.

In late 2004, Khan began tutoring his cousin Nadia who needed help with math using Yahoo!'s Doodle notepad.When other relatives and friends sought similar help, he decided that it would be more practical to distribute the tutorials on YouTube. The videos' popularity and the testimonials of appreciative students prompted Khan to quit his job in finance as a hedge fund analyst at Connective Capital Management in 2009, and focus on the tutorials (then released under the moniker "Khan Academy") full-time.

Multivariable calculus

Multivariable calculus (also known as multivariate calculus) is the extension of calculus in one variable to calculus in more than one variable: the differentiation and integration of functions involving multiple variables, rather than just one.

Typical operations

Limits and continuity

A study of limits and continuity in multivariable calculus yields many counter-intuitive results not demonstrated by single-variable functions. For example, there are scalar functions of two variables with points in their domain which give a particular limit when approached along any arbitrary line, yet give a different limit when approached along a parabola. For example, the function

approaches zero along any line through the origin. However, when the origin is approached along a parabola , it has a limit of 0.5. Since taking different paths toward the same point yields different values for the limit, the limit does not exist.

Continuity in each argument is not sufficient for multivariate continuity: For instance, in the case of a real-valued function with two real-valued parameters, , continuity of in for fixed and continuity of in for fixed does not imply continuity of . As an example, consider

REACT

REACT or React may refer to: