20.1 Current Electric Current Electric current is defined to be the rate at which charge flows. A large current, such as that used to start a truck engine, moves a large amount of charge in a small time, whereas a small current, such as that used to operate a hand-held calculator, moves a small amount of charge over a long period of time. In equation form, electric current I is defined to be ΔΟ I = Δι (20.1) where AQ is the amount of charge passing through a given area in time At . (As in previous chapters, initial time is often taken to be zero, in which case At = 1.) (See Figure 20.2.) The SI unit for current is the ampere (A), named for the French physicist André-Marie Ampère (1775–1836). Since I = AQ/At , we see that an ampere is one coulomb per second: 1A = 1 C/s (20.2) Not only are fuses and circuit breakers rated in amperes (or amps), so are many electrical appliances. Current = flow of charge Figure 20.2 The rate of flow of charge is current. An ampere is the flow of one coulomb through an area in one second.

20.1 Current Electric Current Electric current is defined to be the rate at which charge flows. A large current, such as that used to start a truck engine, moves a large amount of charge in a small time, whereas a small current, such as that used to operate a hand-held calculator, moves a small amount of charge over a long period of time. In equation form, electric current I is defined to be ΔΟ I = Δι (20.1) where AQ is the amount of charge passing through a given area in time At . (As in previous chapters, initial time is often taken to be zero, in which case At = 1.) (See Figure 20.2.) The SI unit for current is the ampere (A), named for the French physicist André-Marie Ampère (1775–1836). Since I = AQ/At , we see that an ampere is one coulomb per second: 1A = 1 C/s (20.2) Not only are fuses and circuit breakers rated in amperes (or amps), so are many electrical appliances. Current = flow of charge Figure 20.2 The rate of flow of charge is current. An ampere is the flow of one coulomb through an area in one second.

College Physics

10th Edition

ISBN:9781285737027

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter18: Direct-Current Circuits

Section: Chapter Questions

Problem 63AP: An electric eel generates electric currents through its highly specialized Hunters organ, in which...

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