Circuits and Electricity
Understand how voltage, current, and resistance interact in electric circuits. From Ohm's law to Kirchhoff's laws, circuit analysis powers modern technology.
Learning Path
Electric Circuits Poster
Visual guide to Ohm's law, series vs parallel configurations, voltage, current, resistance, and power with annotated circuit diagrams and worked examples.
Open →Circuit Calculator
Calculate voltage, current, resistance, and power with Ohm's law. Build series and parallel resistor networks with step-by-step equivalent resistance calculations.
Open →Circuit Builder Lab
Explore series, parallel, and combination circuits with adjustable resistor values. Verify Ohm's law and Kirchhoff's laws with animated current flow and real-time calculations.
Open →Key Formulas
The essential circuit formulas to keep handy.
- Ohm's Law: V = IR
- Power: P = IV = I^2R = V^2/R
- Series: R_total = R1 + R2 + ...
- Parallel: 1/R_total = 1/R1 + 1/R2 + ...
- Series: same current, voltage splits
- Parallel: same voltage, current splits
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Common Questions
What is Ohm's law?
Ohm's law states that V = IR: voltage equals current multiplied by resistance. It holds for ohmic conductors at constant temperature and is the starting point for almost every circuit calculation.
How does current behave differently in series vs parallel circuits?
In a series circuit the same current flows through every component and voltage is divided. In a parallel circuit the voltage across each branch is the same and the total current is the sum of the branch currents.