Circuit Builder
Build a circuit, close a switch and see where voltage, current and power go.
Your circuit
Select a position in the diagram, then choose a component below. Select a switch to open or close it.
Three things to try
Start with one lamp, then add another in series. The same current passes through both, while the battery voltage is shared between them.
Switch to two parallel branches. Each branch sees the full battery voltage, and the branch currents add to the battery current.
Open a switch to interrupt one path. A lamp on that path goes dark, but another closed parallel branch can keep working.
About electric circuits
An electric circuit is a connected path that lets charge move from an energy source through electrical components and back again. Batteries supply a voltage, while loads such as lamps use electrical energy. A switch can interrupt the path and stop the current.
Ohm's law relates voltage, current and resistance in many simple circuits. In a series connection the same current flows through each component; in parallel, each branch has the same voltage across it. These relationships explain why adding a lamp in series differs from adding one alongside another lamp.
Circuit diagrams use symbols to describe connections without copying the physical layout of wires. They are useful in school, repair and electronics design because they make the paths of current easier to reason about. Real lamps and batteries can behave differently from ideal components, so practical circuits also require attention to ratings and safety.