flux

physics

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June 26, 2026

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In physics, "flux" refers to the rate at which a fluid, particles, or energy pass through a given surface. This concept is crucial in understanding phenomena like electric and magnetic fields.1

Electric flux is a measure of the electric field lines passing through an area. If a closed surface contains no net charge, the total electric flux is zero. However, if there is a net charge, the flux is proportional to that charge, as described by Gauss's law.2

Magnetic flux is a measure of magnetic induction, represented by lines of force. A device called a fluxmeter is used to measure magnetic flux density. The term "flux" can also refer to a substance that promotes fusion, such as in soldering, or to a continuous flow or change.341

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principles of physical science
Gauss’s theorem
…elementary area is E, the flux through the element is defined as the product of the magnitude dS and the component of E normal to the element—i.e., the scalar product E · dS. A charge q at the centre of a sphere of radius r generates a field ε =…
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…elementary area is E, the flux through the element is defined as the product of the magnitude dS and the component of E normal to the element—i.e., the scalar product E · dS. A charge q at the centre of a sphere of radius r generates a field ε =…
Read More

spectroscopy
Neutrino detection
…rich in chlorine atoms, the flux from the boron-8 (⁸B) source of solar neutrinos can convert a few of the chlorine-37 (³⁷Cl) atoms to argon-37 (³⁷Ar) atoms with a half-life of 35 days. These atoms can then be detected by nuclear decay counting to determine the flux of the high-energy…
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…rich in chlorine atoms, the flux from the boron-8 (⁸B) source of solar neutrinos can convert a few of the chlorine-37 (³⁷Cl) atoms to argon-37 (³⁷Ar) atoms with a half-life of 35 days. These atoms can then be detected by nuclear decay counting to determine the flux of the high-energy…
Read More