- There Are Two Types Of Elements In An Electric Circuit Active Elements And Passive Elements An Active Element Supplie 1 (114.4 KiB) Viewed 43 times
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There are two types of elements in an electric circuit - active elements and passive elements. An active element supplies energy. A voltage source or a battery is an active element. The emf of a battery is measured using the unit volt (V). A passive element absorbs energy. A resistor is a passive element. The resistance of a resistor is measured using the unit Ohm (S2). There are two fundamental circuit variables - current through a circuit element and voltage across a circuit element. The current through a circuit element is measured using the unit Ampere (A) and the voltage across a circuit element is measure using the unit Volt (V). A simple electric circuit is shown in Figure 1. The emf of the battery is E Volt and the resistance of the resistor is R 12. The current drawn from the battery and the current passing through the resistor are same and is I A. The voltage drop across the resistor is V Volt. The voltage drop across the resistor is exactly equal to the emf of the battery, that is, E = V. The Ohm's Law states that V = IR. If we plot V vs. 1 (taking I as independent variable), we have a straight line passing through the origin and the slop of the line is R. E Figure 1: A simple electric circuit. An ammeter is used to measure current and a voltmeter is used to measure voltage. As shown in Figure 2, an ammeter is connected in series with an element, current through which is to be measured. A voltmeter is connected in parallel with an element, voltage across which is to be measured. If you connect an ammeter in parallel with an element, the meter will be damaged. If you connect a voltmeter in series with an element, it will not give you correct result. So, make sure that an ammeter is not connected in parallel and a voltmeter is not connected in series. Element Figure 2. Connection of ammeter and voltmeter.