Learning Labs / Circuit Quest
Make the connection.
Wire a miniature electronics kit, solve circuit puzzles, and discover why each connection matters.
Lesson 01 / Build your understanding
Complete the loop
Connect both terminals of a source through a lamp and distinguish an open circuit from a closed conducting path.
01 / Concept
Start with the idea.
A source creates a potential difference between its terminals. A lamp can carry steady current only when a complete conducting route connects the source through the lamp and back.
The kit uses a direct-current source and resistive lamps. Wires and a closed switch are ideal zero-resistance connections; each lamp is modeled as a fixed 20 Ω resistor.
Read the reasoning
Conventional current is described from the positive terminal through the loads toward the negative terminal. The source supplies energy; charge circulates rather than being used up by a lamp.
02 / Predict
What do you expect?
Circuit mission / 01
Bring the first lamp to life
Choose two terminals and connect a wire, or select terminals in the 3D kit. Complete a route through Lamp 1 back to the source.
Goal: Lamp 1 has a conducting loop and nonzero power
The tray is ready. Connect your first wire to start building the route.
Your kit is ready to connect.
Use the diagram and terminal labels to build a route. Test it to measure the result and check the mission.
| Part | A → B volts | A → B amps | Power |
|---|---|---|---|
| L1 | — | — | — |
— means an undefined potential, an unmeasured ideal-switch current, or a test that has not run. Floating unpowered resistive loads have zero current and power.
Trace the explanation
Test the circuit to inspect its measurements.
See the labeled wiring diagram
How this circuit model works
The source is ideal DC at 3, 6, or 9 V. Lamps are fixed 20 Ω resistors; the adjustable resistor is 1–200 Ω. Wires and closed switches are ideal zero-resistance connections. Readings describe steady state, without capacitance, inductance, changing filament resistance, battery chemistry, or startup timing.
The source pauses the test above a 1.5 A teaching limit or at a direct source short. Real devices need their actual source, wire, component, and protection characteristics. Lamp glow illustrates relative power, not real-world brightness. Only terminal endpoints connect wires; crossing wires do not form junctions.
05 / Practice
Put the idea to work.
06 / Recap
Take the lesson with you.
- A conducting return path is needed for steady DC current.
- The source provides energy; charge is not consumed by a lamp.
- Voltage is a potential difference between two points.
Check your prediction and solve a practice challenge to complete this lesson.
References & further reading
Keep your curiosity going.
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