Introduction to Resistors
The tiny components that control electricity
The tiny components that control electricity
A resistor is a component that resists the flow of electric current. It's like a narrow pipe that slows down water flow.
Controls how much electricity flows through a circuit
Prevents LEDs and chips from getting too much current
Higher ohms = more resistance = less current
The Ohm is named after Georg Ohm, a German physicist who discovered the relationship between voltage, current, and resistance in 1827!
Electrons flowing through a resistor collide with atoms, converting electrical energy into heat. More resistance means fewer electrons get through.
More current flows through. Electrons move faster, more heat generated.
Less current flows. Electrons are slowed down, less heat produced.
Resistors can get hot! That's why high-power resistors are large and sometimes have heatsinks - they need to dissipate heat safely.
Resistors use colored bands to indicate their value. Each color represents a digit (0-9), and the bands combine to show the resistance.
Big Beautiful Roses Occupy Your Garden But Violets Grow Wildly = 0-9
4-band resistors have 5% tolerance. Precision resistors have 5 bands for more accuracy.
Color codes were invented because printing tiny numbers on small resistors was too difficult. Colors are easier to see and don't wear off as easily!
The most important formula in electronics: V = I × R. Voltage equals Current times Resistance. Knowing any two values lets you calculate the third!
Voltage equals current times resistance. Use this to find voltage.
Current equals voltage divided by resistance. Find how much current flows.
Resistance equals voltage divided by current. Calculate needed resistance.
Ohm's Law works for almost everything! From tiny circuits to power grids, this simple formula helps engineers design safe, efficient electrical systems.
Resistors can be combined in two ways: series (end-to-end) adds resistance, while parallel (side-by-side) reduces it!
Resistances add up. Current has only one path, so it passes through both.
Total is less than smallest! Current splits between paths.
Two identical resistors in parallel give exactly half the resistance. Three give a third. This is useful for creating custom resistance values!
You now understand how resistors limit current, can read color codes, apply Ohm's Law, and know how resistors combine in series and parallel. These essential components are in every electronic device!
Resistors oppose electron flow, limiting current to protect components.
Colored bands indicate resistance value - each color represents a digit.
V = I × R relates voltage, current, and resistance in any circuit.
Series resistors add up; parallel resistors share current and reduce total resistance.
Put your new knowledge into practice!