circuits reviewer

Page 1: Key Concepts in Electrical Systems

Complex Configuration

• Definition: A network where no elements are arranged in series or parallel, allowing for intricate connections that can apply to various circuits.

Iron-Vane Device

• Principle: Operates on the repulsion between like magnetic poles. The system includes one fixed vane and one movable vane in a coil, where the current applied influences the deflection of the movable vane and thereby indicates current levels.

Ladder Network

• Structure: This type of network consists of a series of cascaded series-parallel combinations, visually resembling a ladder's structure.

Measurement Instruments

• Megohmmeter: Used for measuring high resistance levels in the megohm range.

• Series Ohmmeter: An ohmmeter that connects in series with the resistance under test.

• Ohmmeter: A device for measuring resistance levels.

Circuit Types

• Series-Parallel Network: A circuit configuration that contains both series and parallel branches, combining the properties of each.

• Transistor: A three-terminal semiconductor device enabling amplification and switching functions.

• Voltage Divider Supply: A series network utilized to provide varying voltage levels for electronic applications.

Important Terms

• Absolute Zero: The temperature where all molecular motion ceases, equivalent to -273.15°C.

• Circular Mil (CM): A unit for measuring the cross-sectional area of wire; specified as a wire with a diameter of 1 mil.

• Color Coding: A technique using colored bands to indicate resistance values and tolerances.

• Conductance (G): Indicates how easily current flows through a material, measured in siemens (S).

• Cooper Effect: Refers to the pairing of electrons as they move through conductive materials.

• Ductility and Malleability: Physical properties of materials; ductility allows for elongation into wires, while malleability permits reshaping into various forms.

• Memristor: A type of resistor whose resistance value depends on the current passing through it and can retain memory of its last state.

• Temperature Coefficient of Resistance: A value that indicates how resistance changes with temperature, highlighting negative or positive coefficients affecting resistance behavior.

Page 2: Circuit Theory Fundamentals

Resistors and Circuits

• Rheostat: A variable resistance device whose resistance can be changed in a linear or nonlinear manner.

• Superconductor: Materials that can conduct electricity with zero resistance under certain conditions.

• Thermistor: Temperature-sensitive resistive device, where resistance varies with heat.

• Varistor: A nonlinear resistor that responds to high voltage transients.

Circuit Analysis Rules

• Current Divider Rule (CDR): A method for finding current through parallel components without calculating voltage.

• Kirchhoff's Current Law (KCL): The sum of currents at a junction (node) is zero, meaning all incoming current must equal all outgoing current.

• Open Circuit: A broken connection between parts of an electrical network, preventing current flow.

• Parallel Circuit: A setup in which circuit elements share two common connection points.

• Short Circuit: A low-resistance connection which can disrupt normal circuit function.

• Closed Loop and Circuit: Describes systems where current can circulate continuously, ensuring energy flow.

• Internal Resistance: Resistance that naturally exists within energy sources impacting their efficiency and performance.

Voltage and Ratings

• Kirchhoff's Voltage Law (KVL): The total of the voltage gains and losses around a closed loop must equal zero.

• Voltage Divider Rule (VDR): A technique for determining voltage across components in a series without finding current.

• Voltage Regulation (VR): A percentage rating indicating how terminal voltage changes in response to load variations.

Page 3: Electrical Energy & Power

Measurement and Energy Principles

• Efficiency (η): The output to input power ratio, informing about the performance of a system.

• Energy (W): The change in energy state measured in joules, determined by power conversion over time.

• Fuse: A safety device preventing excessive currents in circuits, designed to break the connection when limits are reached.

• Horsepower (hp): A measure of power equal to 746 watts.

• Kilowatt-hour Meter: An instrument measuring total energy consumption over time.

• Ohm's Law: Describes the direct relationship between current, voltage, and resistance in electrical systems.

• Power: The rate of doing work, expressed in watts (J/s).

Current and Charge Dynamics

• Ammeter: A device used to measure current flowing through a series-connected circuit.

• Ampere (A): The unit for measuring electrical current.

• Ampere-hour (Ah): Rating indicating how long a specific current can be drawn from an energy source.

• Cell: The fundamental unit of electrical energy, generated through chemical or solar processes.

• Conductors and Conventional Flow: Conductors allow significant electron flow, with conventional flow defining charge movement based on positive charges.

• Copper: An excellent conducting material due to its physical attributes.

• Coulomb (C): The basic SI unit of electric charge, equivalent to the charge of approximately 6.242 x 10^18 electrons.

Page 4: Atomic Structure and Energy Sources

Atomic Particle Properties

• Electron: A negatively charged particle found within atomic structures, influencing electrical properties.

• Neutron: A neutral particle situated in the atom's nucleus.

• Proton: The positive particle located in the nucleus, helping define atomic number.

• Potential Difference: Represents the voltage difference between two points in a circuit.

Energy Sources

• Primary Cell: Voltage sources that do not recharge once depleted.

• Secondary Cell: Rechargeable sources of voltage, often used in battery technologies.

• Fuel Cell: An eco-friendly energy source producing current through hydrogen and oxygen reactions.

• Solar Cell: Converts light energy into electric energy, harnessing photons from sunlight.

Key Electrical Terms

• Semiconductor: Materials that exhibit conductive properties between insulators and conductors; integral in electronic device manufacture.

• Volt (V): Unit of measure for electrical potential difference; one joule per coulomb of charge.

• Voltage: The electric potential difference driving charge flow within electrical networks.

• Voltmeter: Instrument used for measuring voltage across circuit elements.