Lorentz force  In physics (specifically in electromagnetism) the Lorentz force (or electromagnetic force) is the combination of electric and magnetic force on a point charge due to electromagnetic fields. A particle of charge "q" moving with a velocity v in an electric field E and a magnetic field B experiences a force of (in SI units). Variations on this basic formula describe the magnetic force on a current-carrying wire (sometimes called Laplace force), the electromotive force in a wire loop moving through a magnetic field (an aspect of Faraday's law of induction), and the force on a charged particle which might be traveling near the speed of light (relativistic form of the Lorentz force). Historians suggest that the law is implicit in a paper by James Clerk Maxwell, published in 1865. Hendrik Lorentz arrived in a complete derivation in 1895, identifying the contribution of the electric force a few years after Oliver Heaviside correctly identified the contribution of the magnetic force. The force F acting on a particle of electric charge "q" with instantaneous velocity v, due to an external electric field E and magnetic field B, is given by (in SI units):  where × is the vector cross product (all boldface quantities are vectors). In terms of cartesian components, we have:  In general, the electric and magnetic fields are functions of the position and time. Therefore, explicitly, the Lorentz force can be written as:  in which r is the position vector of the charged particle, "t" is time, and the overdot is a time derivative. A positively charged particle will be accelerated in the "same" linear orientation as the E field, but will curve perpendicularly to both the instantaneous velocity vector v and the B field according to the right-hand rule (in detail, if the fingers of the right hand are extended to point in the direction of v and are then curled to point in the direction of B, then the extended thumb will point in the direction of F). The term "q"E is called the electric force, while the term "q"(v × B) is called the magnetic force. According to some definitions, the term "Lorentz force" refers specifically to the formula for the magnetic force, with the "total" electromagnetic force (including the electric force) given some other (nonstandard) name. This article will "not" follow this nomenclature: In what follows, the term "Lorentz force" will refer to the expression for the total force.