6–70 Supercapacitor Supercapacitors have very large capacitances (typically from 0.1 to 3000 F), very long charge-holding times, and small sizes, making them useful in nonbattery backup power applications.

To measure its capacitance, a supercapacitor is charged to an initial voltage vOð0Þ = 6 V. At t = 0, the device undergoes a constant current discharge of iD = 3 mA. After 1 hour, the voltage remaining on the capacitor is 3 V. Find the device’s capacitance.