Unit pAh picoampere-hour Electric Charge In the field of electric charge, PAh (petaampere-hour) is a unit used to measure the quantity of electric charge. It indicates the charge transferred by a constant current of one petaampere (1 PA = 1 x 10^15 amperes) flowing for one hour. The ampere-hour (Ah) is the base unit of electric charge, which measures the amount of charge transferred by a constant current of one ampere flowing for one hour. The PAh is derived from this base unit by including the "peta" prefix, which denotes a multiplication factor of 10^15. Therefore, 1 PAh is equal to 10^15 ampere-hours (Ah). The PAh unit is not commonly used in everyday applications, as it represents an extraordinarily large quantity of electric charge, typically only encountered in extremely high-power systems or large-scale scientific research. Smaller units like ampere-hours (Ah), milliampere-hours (mAh), and microampere-hours (µAh) are more common in practical applications such as batteries and electric circuits.