1. Circuit Elements Electric circuit is the interconnection of circuit elements ActivePassive Not capable of generating energy e.g. resistor, inductor, capacitor Here, we will look at: 1. Voltage and current sources (active elements) 2. Resistors (passive element) Later in the course we will have a look at capacitors and inductors (energy storage elements) Capable of generating energy Voltage and current sources e.g. batteries, generators

2. Circuit Elements Independent sources Voltage and current sources (Active elements) Dependent sources Voltage or current independent of other circuit elements Voltage or current is controlled by other voltage or current

3. Circuit Elements Independent sources Voltage source Delivers specified voltage at terminal regardless of circuit connected to it Current delivered (or drawn) depends on the circuit connected to it v V

4. Circuit Elements Independent sources Current source Delivers specified current at terminal regardless of circuit connected to it Voltage across it depends on the circuit connected to it i

5. Circuit Elements Dependent sources Voltage-Controlled voltage source +-+- v s =  v x Dependent Voltage sources +-+- v s =  i x Current-Controlled voltage source

6. Circuit Elements Dependent sources Current-Controlled current source Dependent Current sources Voltage-Controlled current source i s =  i x i s =  v x