Electric Circuit A continuous and closed path of an electric current is called an electric circuit. Electric current is expressed by the amount of charge flowing through a particular area in unit time. Direction of Electric current Electric current was considered to be the flow of positive charges.Conventionally, in an electric circuit, the direction of electric current is taken as opposite to the direction of the flow of electrons, which are negative charges.If a net charge Q flows across any cross-section of a conductor in time t, then the current I, through the cross-section is: I = Q/t The SI unit of electric charge is Coulomb (C).The SI unit of electric current is ampere (A). One ampere One ampere is constituted by the flow of one coulomb of charge per second. Ammeter An instrument called ammeter measures electric current in a circuit. It is always connected in series in a circuit through which the current is to be measured...