Difference in electric potential between two points in space
"Potential difference" redirects here. For other uses, see
Potential .
Voltage Common symbols
V , ∆V , U , ∆U SI unit volt In SI base units kg⋅m2 ⋅s−3 ⋅A−1 Derivations from other quantities
Voltage = Energy / charge Dimension
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T
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{\displaystyle {\mathsf {M}}{\mathsf {L}}^{2}{\mathsf {T}}^{-3}{\mathsf {I}}^{-1}}
Voltage , also known as (electrical) potential difference , electric pressure , or electric tension is the difference in electric potential between two points.[1] [2] In a static electric field , it corresponds to the work needed per unit of charge to move a positive test charge from the first point to the second point. In the International System of Units (SI), the derived unit for voltage is the volt (V) . [3] [4] [5]
The voltage between points can be caused by the build-up of electric charge (e.g., a capacitor ), and from an electromotive force (e.g., electromagnetic induction in a generator ).[6] [7] On a macroscopic scale, a potential difference can be caused by electrochemical processes (e.g., cells and batteries), the pressure-induced piezoelectric effect , and the thermoelectric effect . Since it is the difference in electric potential, it is a physical scalar quantity .[8]
A voltmeter can be used to measure the voltage between two points in a system.[9] Often a common reference potential such as the ground of the system is used as one of the points. A voltage can be associated with either a source of energy or the loss, dissipation, or storage of energy.
^ Cretì, Anna; Fontini, Fulvio (2019-05-30). Economics of Electricity: Markets, Competition and Rules . Cambridge University Press. p. 18. ISBN 978-1-107-18565-4 .
^ Tregub, Stanislav (2020-08-08). Theory of Energy Harmony: Mechanism of Fundamental Interactions . Stanislav Tregub. p. 26. ISBN 978-5-6044739-2-4 .
^ David B. Newell, Eite Tiesinga (August 2019). The International System of Units (SI) (PDF) (Report). National Institute of Standards and Technology. p. 31. Retrieved 2 January 2024 .
^ Holloway, Michael D.; Holloway, Emma (2020-12-09). Dictionary of Industrial Terminology . John Wiley & Sons. p. 1259. ISBN 978-1-119-36410-8 .
^ Aslam, Dr S.; Sharma, Dr Pradosh Kumar; Rahul, Satyakam; Saluja, Dr Hitanshu (2024-01-26). Integrating Electrical Systems With Intelligent Computing . Academic Guru Publishing House. p. 17. ISBN 978-81-19843-91-6 .
^ Demetrius T. Paris and F. Kenneth Hurd, Basic Electromagnetic Theory , McGraw-Hill, New York 1969, ISBN 0-07-048470-8 , pp. 512, 546
^ P. Hammond, Electromagnetism for Engineers , p. 135, Pergamon Press 1969 OCLC 854336 .
^ Experts, Disha (2017-08-29). 10 in One Study Package for CBSE Physics Class 12 with 5 Model Papers . Disha Publications. p. 64. ISBN 978-93-86323-72-9 .
^ International, Petrogav. Production Course for Hiring on Offshore Oil and Gas Rigs . Petrogav International. p. 328.