Unit 3: Electric Circuits

Voltage

It is the difference in electric potential between two points in a circuit. It is measured in volts (V) and is represented by the symbol "V".

Current

It is the flow of electric charge through a circuit. It is measured in amperes (A) and is represented by the symbol "I". It is the rate at which charge flows through a circuit.

Resistance

It is the opposition to the flow of electric current in a circuit. It is measured in ohms (Ω) and is represented by the symbol "R". It is determined by the material and dimensions of the conductor.

Power

It is the rate at which energy is transferred in a circuit. It is measured in watts (W) and is represented by the symbol "P". Power is calculated by multiplying voltage and current.

Frequency

It is the number of cycles per second in an alternating current (AC) circuit. It is measured in hertz (Hz) and is represented by the symbol "f". It determines the speed at which the AC signal alternates.

Impedance

It is the total opposition to the flow of electric current in a circuit. It is measured in ohms (Ω) and is represented by the symbol "Z". It is a combination of resistance, capacitance, and inductance.

Current

It is the flow of electric charge through a conductor.

Direct current (DC)

Current flows in one direction only.

Alternating current (AC)

Current changes direction periodically.

Ohm's Law

It states that the current through a conductor between two points is directly proportional to the voltage across the two points, and inversely proportional to the resistance between them.

V \= I * R

Ohm's Law Formula

Resistance

it is the opposition that a material or a circuit offers to the flow of electric current.

Fixed resistors

These have a fixed resistance value and cannot be changed.

Variable resistors

These have a variable resistance value and can be adjusted.

Thermistors

These have a resistance that varies with temperature.

Light-dependent resistors

These have a resistance that varies with light intensity.

Circuit measuring tools

These are used to measure various electrical parameters in a circuit.

Multimeter

A versatile tool that can measure voltage, current, and resistance. It is used to troubleshoot circuits and check the continuity of wires and components. They come in both analog and digital versions.

Oscilloscope

Used to measure and display voltage signals over time. It is used to analyze waveforms and diagnose problems in circuits. They come in both analog and digital versions.

Function generator

Used to generate various types of waveforms such as sine, square, and triangle waves. It is used to test circuits and simulate different types of signals.

Logic analyzer

Used to capture and analyze digital signals in a circuit. It is used to troubleshoot digital circuits and analyze the behavior of digital signals.

Power supply

Used to provide a constant voltage or current to a circuit. It is used to test circuits and power electronic devices.

LCR meter

Used to measure the inductance, capacitance, and resistance of a circuit. It is used to test and design circuits that use inductors, capacitors, and resistors.

Series circuit

It is a circuit in which the components are connected in a single loop, so the current flows through each component in turn.

Parallel circuit

It is a circuit in which the components are connected in separate branches, so the current divides between them.

Electrical circuits

These are often used to convert electrical energy into other types of energy.

Kirchhoff's Voltage Law (KVL)

It is a fundamental law in electrical engineering that states that the sum of all voltages around a closed loop in a circuit must be zero. This law is based on the principle of conservation of energy, which states that energy cannot be created or destroyed, only transferred from one form to another.

Kirchhoff's Current Law (KCL)

it is a fundamental law in electrical engineering that states that the total current entering a node or junction in a circuit must be equal to the total current leaving that node or junction.

Electromotive forces

the voltage generated by a battery or other source of electrical energy.

1/C_total \= 1/C_1 + 1/C_2 + ... + 1/C_n

Capacitors in Series Formula

C_total \= C_1 + C_2 + ... + C_n

Capacitors in Parallel Formula

RC circuits

These are circuits that contain a resistor and a capacitor. These circuits are used in a variety of applications, including filters, timing circuits, and oscillators.