Resistors - All You Need to Know | Ohm's Law, Color Code, Power Rating and Types

Why doesn't the tiny LED on your phone charger burn out the moment you plug it in? Meet the resistor: the small striped part that controls the current in every circuit you own. 👩‍🏫 Teachers: a ready-to-assign Edpuzzle for this video (20 questions): https://edpuzzle.com/media/6addebb61d... In this video you'll learn: What a resistor does, and Ohm's law: V = IR What decides resistance: material, length and thickness (R = ρL/A) How temperature changes resistance: metals vs. NTC and PTC thermistors Current limiting for an LED and the potential divider Power rating: why the same 500 Ω resistor is safe at 5 V (0.05 W) but burns out at 120 V (28.8 W) Tolerance: why a 1000 Ω ±5% resistor can be anywhere from 950 Ω to 1050 Ω Types of resistors: carbon film, metal film, wirewound, potentiometers, LDRs and thermistors The resistor color code, with worked examples: 56 kΩ ±5%, 47 kΩ ±1%, and a 22 kΩ challenge Circuit symbols: the box (IEC) and the zigzag (ANSI) Perfect for Principles of Engineering (PLTW POE), physics and electronics classes, and anyone getting started with Arduino and electronics. More free STEM lessons and resources: https://stemeducation.tech Chapters: 0:00 Why resistors matter 0:36 What is a resistor? 1:20 Ohm's law: V = IR 2:07 Material, length and thickness (R = ρL/A) 3:20 Resistance and temperature: NTC vs PTC 4:10 What resistors do in a circuit 4:30 Power rating: same 500 Ω, two jobs 5:36 Tolerance 5:54 Types of resistors 6:28 Potentiometers, LDRs and thermistors 7:07 The resistor color code 8:12 Circuit symbols: box vs zigzag 8:26 Recap