Basic DC Circuit Concepts Quiz

Study Notes

Basic DC Circuit Concepts

Alessandro Volta (1745-1827): Italian physicist who invented the electric battery, enabling continuous electric flow. Invented the capacitor.
Andre-Marie Ampere (1775-1836): French mathematician and physicist who formulated the laws of electromagnetics. Developed a method to measure electric current. Defined electrodynamics. Unit of electric current is named after him.
Electric Circuit: An interconnection of electrical devices (elements) used to transfer energy.
Simple Circuit Components: Battery, lamp, and connecting wires are basic components.
SI Units: System of units used throughout the text, utilizes prefixes based on powers of 10 to relate larger/smaller units to the basic unit.
Charge and Current:
- Electrons have a negative charge (-).
- Protons have a positive charge (+).
- Neutrons are neutral.
- Electric current (I) is the rate of charge flow (measured in amperes).
Direct Current (DC): Constant current flow.
Alternating Current (AC): Sinusoidally varying current.
Voltage: Energy required to move a unit of charge between two points. Measured in volts (V).
Power: Rate of energy transfer or dissipation. Measured in watts (W). Power = voltage × current.
Passive Sign Convention: Current entering a positive terminal results in positive power (absorbed); current entering negative terminal results in negative power (supplied).
Circuit Elements: An electric circuit consists of passive and active elements.
- Passive elements (resistors, capacitors, inductors) don't generate energy.
- Active elements (generators, batteries, operational amplifiers) generate energy.
Independent Sources: Provide a specific voltage or current that isn't dependent on other circuit variables.
Dependent Sources: Source quantity (voltage or current) is controlled by another voltage or current in the circuit. Usually represented by diamond-shaped symbols.
- Various types: voltage-controlled voltage source (VCVS), current-controlled voltage source (CCVS), voltage-controlled current source (VCCS), and current-controlled current source (CCCS).

Problems and Examples (from provided pages)

Problem 1: Calculate power received/delivered by a specific component in a given circuit. Data for other elements given, algebraic sum should equal zero.
Problem 2: Calculate current drawn by a 1.5kW electric heater plugged into 120V.
Problem 3: Calculate power absorbed by different elements within circuit (diagram provided).
Problem 4: Determine a circuit current (I0) (diagram provided).
Problem 5: Determine voltage (Vo) in a circuit (diagram provided).