noun
electromotive force; EMF
Technical term in physics and electrical engineering; refers to the voltage generated by a battery or changing magnetic field.
電池の起電力を測定する。
Measure the electromotive force of the battery.
コイルに磁石を近づけると起電力が生じる。
An electromotive force is generated when a magnet is brought near the coil.
電位差 (potential difference) is a more general term; 起電力 specifically refers to the energy source driving current.
Compound of 起 (ki, 'to rise, generate') + 電力 (denryoku, 'electric power'). A straightforward technical coinage.