Circuit Construction Kit: AC

Challenge 1: Build an AC Resistor Circuit

LEVEL 1 / 6

Drag components from the left palette onto the board, snap terminals into a loop, and verify the current.

🔢 NCERT AC Circuit Solver

Problem Topic

🧰 Circuit Setup

Palette

⚡ Quick Circuit Templates

Resistor

🔌 Interactive Circuit Workbench Loop: Open

Show Charges: Electrons (e⁻) Conventional (→) Values Labels

Drag components anywhere • Snap terminals together

📊 Live Analysis

Real-Time

Source Voltage (V_rms) AC / DC Source

0.00 V

RMS Voltage Effective

Circuit Current (I_rms) Loop Current

0.000 A

Peak (I₀): 0.000 A Total Z: 0.0 Ω

Phase Angle & Power AC Network

0.0°

Power Factor: 1.000 f₀: -- Hz

Dual-Trace Scope Cyan: V(t) | Gold: I(t)

X_L = 0.0 Ω | X_C = 0.0 Ω

Z = √(R² + (X_L − X_C)²) = 0.0 Ω

I_rms = V / Z = 0.000 A

📋 Observation Data Logger

Trial #	Source V (V)	f (Hz)	Impedance Z (Ω)	Current I (A)	Phase φ (°)	Power Factor	Active Power (W)

Circuit Construction Kit: AC allows you to build arbitrary electrical circuits with alternating current (AC) and direct current (DC) sources, resistors, inductors, capacitors, light bulbs, switches, fuses, and real-world everyday objects.

Observe the back-and-forth sinusoidal oscillation of electrons in alternating current circuits, measure phase angles between voltage and current, explore resonance phenomena ($X_L = X_C$), and analyze how inductive and capacitive reactances vary with frequency.

Core AC Relationships:

Inductive Reactance: $X_L = 2\pi f L = \omega L$ (Current lags voltage by 90°)
Capacitive Reactance: $X_C = \frac{1}{2\pi f C} = \frac{1}{\omega C}$ (Current leads voltage by 90°)
Series RLC Impedance: $Z = \sqrt{R^2 + (X_L - X_C)^2}$
Ohm's Law for AC: $I_{rms} = \frac{V_{rms}}{Z}, \quad I_0 = I_{rms}\sqrt{2}$
Phase Angle: $\tan\phi = \frac{X_L - X_C}{R}$
Resonant Frequency: $f_0 = \frac{1}{2\pi\sqrt{LC}}$ (Where $X_L = X_C$ and $Z = R$)
Power Factor & Real Power: $\cos\phi = \frac{R}{Z}, \quad P = V_{rms} I_{rms} \cos\phi$

Interactive Operations:

Drag from Left Palette: Drag any component from the left palette directly onto the playarea canvas. You can also click a tool to place it on the board.
Connecting Terminals: Drag one terminal handle (circle) close to another terminal. When within snapping range, they snap together into a shared junction.
Moving Components: Drag the body of any component to reposition it. Dragging a junction moves all attached components in unison.
Disconnecting (Scissors): Click on any shared junction. A scissors icon (✂️) will appear right at the junction. Click it to cut the connection!
Tuning Values: Click on any component to inspect and edit its value in the left sidebar inspector.
Live Analysis: Monitor real-time RMS source voltage, branch currents, AC impedance, phase angle, and oscilloscope traces.

Lab Exercises:

Pure Resistor vs AC: Connect an AC source and resistor. Observe that current and voltage are in phase ($\phi = 0^\circ$).
RL Circuit Phase Lag: Add an inductor in series. Note how increasing frequency increases $X_L$, reducing current and causing current to lag.
RC Circuit Phase Lead: Connect an AC source and capacitor. Note how increasing frequency decreases $X_C$, increasing current.
Resonance Peak: Build a Series RLC loop. Adjust AC frequency until $f = f_0$. Observe that impedance reaches its minimum ($Z = R$), current peaks, and the lamp shines brightest!

Q: Why does the bulb glow pulsatingly?
Instantaneous electrical power is $p(t) = i(t)^2 R$. Since $i(t)$ oscillates at frequency $f$, power pulsates at $2f$.

Q: Why did my fuse blow?
The fuse element has a rated threshold of 4.0 A. If current exceeds 4.0 A, the fuse opens the circuit!

Q: Can I build parallel circuits?
Yes! Snap multiple wires to the same junction to create parallel branches.

Challenge 1: Build an AC Resistor Circuit

🔢 NCERT AC Circuit Solver

📋 Observation Data Logger

Circuit Construction Kit: AC Guide

Challenge Completed!