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For designing high-field electromagnets, the Lorentz force on coils must be computed to ensure a support structure is feasible, and the inductance should be computed to evaluate the stored energy. Also, the magnetic field and its variation…

Analytically the forces and torques on a coil in a field of magnetic flux density can be calculated one of two ways. The line integral can be conducted along the coil's wire, summing up the differential force contribution. For each…

The reduction of magnetic forces on electromagnetic coils is an important consideration in the design of high-field devices such as the stellarator or tokamak. Unfortunately, these forces may be too time-consuming to evaluate by…

We consider the forces acting on electrons in magnetic field including the constraints and a condition arising from quantum mechanics. The force is calculated as the electron mass, $m_e$, multiplied by the total time-derivative of the…

In this paper we calculate the magnetic and electric self-forces, induced by the conical structure of a cosmic string space-time, on a long straight wire which presents either a constant current or a linear charge density. We also show how…

Teaching magnetism is one of the most challenging topics at undergraduate level in programmes with scientific background. A basic course includes the description of the magnetic interaction along with empirical results such as the…

Self-gravitational force calculation for infinitesimally thin disks is important for studies on the evolution of galactic and protoplanetary disks. Although high-order methods have been developed for hydrodynamic and magneto-hydrodynamic…

The use of high-temperature superconductors in electric machines offers potentially large gains in performance compared to conventional conductors, but also comes with unique challenges. Here, the electromagnetic properties of…

We develop an approach to calculate the self-force on a charged particle held in place in a curved spacetime, in which the particle is attached to a massless string and the force is measured by the string's tension. The calculation is based…

We present an explicit theoretical framework for constructing artificial modular coils based solely on equilibrium properties, achieved through the formulation of a current potential defined on flux surfaces. We demonstrate that key…

The single-turn coil method is a destructive pulsed magnet for generating over 100 T with a few $\mu$-second pulse duration, and it inevitably causes the coil to explode. The temporal and spatial distributions of the electric current and…

'Coil design' is an inverse problem in which arrangements of wire are designed to generate a prescribed magnetic field when energized with electric current. The design of gradient and shim coils for magnetic resonance imaging (MRI) are…

Despite 180 years of theory on magnetism, it appears that the practice of calculating forces on magnetic media is ambiguous, as illustrated by a recent article by Casperson. Potentially troubling issues include: Which field B or H should be…

In a watt balance experiment, separate measurements of magnetic force and induced electric potential in a conductor in a magnetic field allow for a virtual comparison between mechanical and electrical powers, which leads to and an accurate…

We present our calculation results for organic magnetic electrides. In order to identify the `cavity' electrons, we use maximally-localized Wannier functions and `empty atom' technique. The estimation of magnetic coupling is then performed…

In the joule balance developed at National Institute of Metrology (NIM), the dynamic phase of a watt balance is replaced by the mutual inductance measurement in an attempt to provide an alternative method for the kg redefinition. But for…

Although the H-formulation has proven to be one of the most versatile formulations used to accurately model superconductors in the finite element method, the use of vector dependent variables in non-conducting regions leads to unnecessarily…

We make progress towards a 3D finite-element model for the magnetization of a high temperature superconductor (HTS): We suggest a method that takes into account demagnetisation effects and flux creep, while it neglects the effects…

In this paper we discuss the phenomenon of resonance that we predict will occur when a superconducting coil is submitted simultaneously to a magnetic field and to an external force. When both the force and the magnetic field are constant in…

Superconductors have been being applied to a variety of large-scale power applications, including magnets, electric machines, and fault current limiters, because they can enable a compact, lightweight and high efficiency design. In…