Lesson21Voltage电压,Asyouhaveseen,thereisaforceofattractionbetweenapositiveandanegativecharge.Acertainamountofenergymustbeexertedintheformofworktoovercometheforceandmovethechargesagivendistanceapart.Alloppositechargespossessacertainpotentialenergybecauseoftheseparationbetweenthem.Thedifferenceinpotentialenergyofthechargesisthepotentialdifference.,Asyouhaveseen,thereisaforceofattractionbetweenapositiveandanegativecharge.正如你所知的，正电荷和负电荷之间存在吸引力。Acertainamountofenergymustbeexertedintheformofworktooverc
