Constants   Equations   Subjects   Periodic Table   Conversions   SI Units   Symbols Science Subjects Physics : Electricity - Current and Charge Category Select | Questions   An electric current (I) is the flow of electrons (not attached to a specific ion) in a metal - much the same way as the current in a river is the flow of water particles. This flow is called charge. The ampere (A) is the unit of electric current.   Charge (Q) is measured in coulombs (C). One coulomb of charge is the charge which passes any given point in a circuit when a current of one amp flows for one second. 1C = 1As-1. For example, a current of 4A flowing for 10s will mean that a total charge of 4 x 10 = 40C has passed that point. This can be expressed with the following equation:       Questions (Answers | Top) 1 A current of 12A flows for 2 minutes past a point in a circuit. How much charge has passed? 2 How long would a current of 5A need to flow for if a charge of 150C passes a point in a circuit? 3 What current was flowing if a charge of 10C passes a point in a circuit in 2s?     Answers (Questions | Top) 1 Q = It = 12x2x60 = 1440C 2 t = Q/I = 150C/5A = 30s 3 I = Q/t = 10C/2s = 5A     If you have anything to contribute, simply e-mail it to me at science@tcaep.co.uk. I look foward to hearing from you!

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