The abhenry (abbreviated abH) is the unit of electromagnetic inductance in the cgs (centimeter/gram/second) system of units. It is equivalent to 10^-9 henry. In a 1-abH inductance, a current that increases or decreases at one abampere per second (1 abA/s) will produce an electromotive force (EMF) of one abvolt (1 abV). It is unusual to See: An inductance as large as one henry (1 H) in the real world, but a 1-abH inductance is small, and is not uncommon. In fact, 1 abH is the equivalent of one nanohenry (1 nH), an often-used unit of inductance, especially at ultra-high and microwave radio frequencies. The henry is the standard unit of inductance in the International System of Units (SI). In practical applications, the microhenry (µH) and the nanohenry (nH) are most often used to quantify inductance. For comparison, 1 µH = 10^-6 H and 1 nH = 10^-9 H. Thus, 1 abH = 0.001 µH = 1 nH. Also See: Inductance,Henry,Cgs or Small-Unit Metric System, and International System of Units (SI)