IEVref: 121-11-79 ID: Language: en Status: Standard Term: loop voltage Synonym1: loop tension Synonym2: Synonym3: Symbol: UlUm Definition: scalar quantity equal to the time derivative of the line integral of the magnetic vector potential along a closed path C in which charge carriers can be displaced ${U}_{\text{l}}=-\frac{\text{d}}{\text{d}t}{\oint }_{\text{C}}A\text{d}r=-\frac{\text{d}}{\text{d}t}{\int }_{\text{S}}B\cdot {e}_{\text{n}}\text{d}A=-\frac{\text{d}}{\text{d}t}\Psi$ where A is the magnetic vector potential at a point of the path C, dr is a vector line element of C, B is the magnetic flux density at a point on a surface S delimited by the curve C, endA is a vector surface element of S, Ψ is the total flux through this surface, and t is time Note 1 to entry: The loop voltage is often wrongly denoted as the induced voltage; this is only true when no current is flowing through the path C. Note 2 to entry: The coherent SI unit of the loop voltage is volt, V = s−3 m2 kg A−1. Publication date: 2021-03 Source: Replaces: Internal notes: CO remarks: TC/SC remarks: VT remarks: Domain1: Domain2: Domain3: Domain4: Domain5: