KinexiaLEARN PHYSICS

Circuit Lab Simulator

This is your virtual electronics bench. Place a battery, add bulbs in series or parallel, flip the switch, and watch live ammeter and voltmeter readings. Every reading must obey Ohm's law and Kirchhoff's laws — verify each one, and you will understand circuits better than any amount of reading alone.

VR
Current 120.0 mAPower 1.44 W

Controls

  • Battery voltage: The battery voltage driving the circuit, in volts.
  • Bulb resistance: Resistance of each bulb, in ohms.
  • Circuit layout: One bulb, two in series, or two in parallel.
  • Switch: Close or open the switch to start or stop current.
  • Reset: Restore the default circuit.

The physics

Assumptions

  • Ideal wires with zero resistance
  • Ideal battery with no internal resistance
  • Bulbs modeled as fixed ohmic resistors
  • Steady DC — no capacitance or inductance effects

Guided activity

  1. Build a single-bulb circuit with 6 V and 12 Ω. Predict the current with Ohm's law, then check the ammeter.

  2. Add a second identical bulb in series. What happens to the current and to each bulb's brightness? Why?

  3. Rewire the two bulbs in parallel. Compare the total current with the series case.

  4. Vary the voltage and plot current vs voltage — what shape is the graph, and what does its slope mean?

Challenge questions

  1. Two bulbs in series share the voltage; two in parallel share the current. Explain both using Kirchhoff's laws.

  2. A 60 W and a 100 W bulb (rated at 120 V) are wired in series across 120 V. Which glows brighter, and why is it the opposite of what you expect?

  3. Where does the 'lost' energy go in a resistor? Trace it from electrical to thermal.