The abfarad (abbreviated abF) is the unit of electromagnetic capacitance in the cgs (centimeter/gram/second) system of units. If a charge of one abcoulomb (1 abC) produces a potential difference of one abvolt (1 abV) in a capacitance, then that capacitance is 1 abF.
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A capacitance as large as 1 abF is unknown. It is equivalent to 10 9 farads. The farad (F) is the standard unit of capacitance in the International System of Units ( SI ). Even this unit is large; a 1-F capacitor is almost never found in the real world.
In practical applications, the microfarad (µF) and the picofarad (pF) are most often used to quantify capacitance; the abfarad is rarely seen in literature. For comparison, 1 µF = 10 -6 F and 1 pF = 10 -12 F. Thus, 1 abF = 10 15 µF = 10 21 pF.