Inductance is the tendency of an electrical conductor to oppose a change in the electric current flowing through it. The electric current produces a magnetic field around the conductor. The magnetic field strength depends on the magnitude of the electric current, and follows any changes in the magnitude of the current. From Faraday's law of induction, any change in magnetic field through a circuit induces an electromotive force (EMF) (voltage) in the conductors, a process known as electromagnetic induction. This induced voltage created by the changing current has the effect of opposing the change in current. This is stated by Lenz's law, and the voltage is called back EMF.

विद्युतचुम्बकत्व एवं इलेक्ट्रॉनिक्स में, प्रेरकत्व (inductance) ए.सी.(प्रत्यावर्ति धारा)परिपथों का वह गुण है, जिसके कारण वह विद्युत धारा मान में होने वाले परिवर्तनों का विरोध करता है इसका प्रतीक L तथा मात्रक हेनरी होता है प्रतिरोधों की भांति, इंडक्टर्स को भी समूहन की जरूरत पड़ती है