Interactive Physics
Learn how circuits work — explore Ohm's Law, series & parallel circuits, power, voltage dividers, and more. Build your own and test it with a real backend simulation engine.
Lesson 01 — Basics
A circuit is a closed loop that allows electric current to flow. It needs a power source, a conductive path, and a load to do useful work.
Lesson 02 — Ohm's Law
The relationship between voltage, current, and resistance — the foundation of all circuit analysis.
Lesson 03 — Series
In a series circuit, components are connected end-to-end in a single path. The same current flows through every component.
Lesson 04 — Parallel
In a parallel circuit, components share the same two nodes. Each branch has the same voltage but can carry different currents.
Lesson 05 — Power & Energy
Power is the rate of energy transfer (watts). Energy is power sustained over time — what you actually pay for on your electricity bill (kilowatt-hours).
Lesson 06 — Voltage Divider
Two resistors in series split the supply voltage proportionally. Vout tapped between them scales with the ratio of R2 to the total resistance.
Lesson 07 — Electric Potential
Electric potential is the electric potential energy stored per unit charge at a point. Voltage is the difference in potential between two points — it drives current to flow.
Lesson 08 — Complex Networks
Real circuits often combine series and parallel groups in multiple layers. The key technique is progressive reduction — always start with the innermost (most nested) series or parallel group, replace it with a single equivalent resistor, then work outward until one resistor remains.
Lesson 08A
A parallel pair feeds into a series resistor — the simplest mixed topology.
( R1 ∥ R2 ) — R3Lesson 08B
A series resistor followed by a parallel block where one branch itself contains two series resistors — 3-level reduction.
R1 — [ R2 ∥ (R3+R4) ]Lesson 08C
Two parallel branches, each containing two series resistors — reduce each branch first, then combine in parallel.
( R1+R2 ) ∥ ( R3+R4 )Circuit Lab
Configure a circuit and simulate — results come from the backend calculation engine.
Series Circuit