In this lesson our instructor talks about electric circuits. First, he discusses electric circuits in general, resistor, and components of circuit diagrams. Then he talks about Kirchhoff's two parts circuit laws, resistor in series, and resistor in parallel. In addition, he lectures on voltmeter, ammeter, direct current, and alternating current. Four complete example problems round up this lesson
Current always requires a return path. Every device that uses electricity must have a complete circuit back to the voltage source.
A resistor is a fundamental component of a circuit. It provides a resistance on an otherwise equipotential line of wire.
Make sure you familiarize yourself with all the different symbols used in writing circuit diagrams.
To help us analyze circuits we have Kirchoff's circuit laws: a pair of laws to help us understand what's going on in a circuit.
Current law: The current entering any point is equal to the current leaving that point.
Voltage law: The sum of the electric potential differences (voltages) of any loop is zero.
Resistors in series (end-to-end) have an equivalent resistance of just adding their resistances together.
Req=R1 +R2 +R3.
Resistors in parallel (the circuit splits to get to each of them, then comes back together afterwards) have an equivalent resistance that can be found from the below equation:
A voltmeter measures the voltage between two points. It is hooked up in parallel to the circuit.
An ammeter measures the current passing through a section. It is hooked up in series to the circuit.
Direct current (DC) is a steady, constant voltage. Alternating Current (AC) is a varying voltage, where it flips back and forth between positive and negative electric potentials.
Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.
This book includes a set of features such as Analyzing-Multiple-Concept Problems, Check Your Understanding, Concepts & Calculations, and Concepts at a Glance. This helps the reader to first identify the physics concepts, then associate the appropriate mathematical equations, and finally to work out an algebraic solution.