Electrical Circuits
AC Circuit Design
XL = 2π · f · L
Inductive reactance of an AC circuit at a target frequency and inductance.
Calculate →Capacitor Design
C = ε₀ · εr · A / d
Capacitance of parallel-plate and cylindrical capacitors from geometry and dielectric.
Design →Capacitors in Series & Parallel
1/Cs = Σ 1/Ci · Cp = Σ Ci
Equivalent capacitance for arbitrary N-capacitor series and parallel networks.
Calculate →Inductor Design
L = μ · N² · A / ℓ
Solenoid, toroidal, and flat-spiral air-coil inductance from turns and core geometry.
Design →Ohm's Law
V = I · R · P = V · I
Voltage, current, resistance, and power for a DC resistive circuit — solve any pair.
Calculate →RC & RL Time Constant
τ = R · C · τ = L / R
Charge, discharge, and settling time for RC and RL filter circuits.
Calculate →Resistors in Series & Parallel
Rs = Σ Ri · 1/Rp = Σ 1/Ri
Equivalent resistance for arbitrary N-resistor series and parallel networks.
Calculate →Voltage Divider
Vout = Vin · R2 / (R1 + R2)
Output voltage of a two-resistor voltage divider at a specified input.
Calculate →Wind Turbine Power Generator
P = ½ · ρ · A · v³ · Cp
Turbine power from rotor swept area, wind speed, and performance coefficient.
Calculate →Electrical engineering and electronics calculators for DC and AC circuit analysis: Ohm's law, capacitor and inductor design (parallel-plate, cylindrical, spiral coil), capacitors and resistors in series and parallel, AC inductive reactance, RC and RL time constants, voltage dividers, and wind-turbine power output.
Useful for hobby electronics, EE coursework, and quick circuit checks during prototyping or schematic review.
When to use these calculators
Use Ohm's law and the series/parallel network calculators when sizing resistors and capacitors for a discrete circuit. Use the RC/RL time-constant calculator to spec a filter cutoff or charge-discharge time. Use the AC Circuit calculator to compute inductive reactance for AC analysis.
These are educational tools; SPICE simulation remains the standard for complex circuit verification.
Frequently Asked Questions
- What is Ohm's law?
- Ohm's law states V = I × R: the voltage across a resistor equals the current through it times the resistance. The Ohm's Law calculator solves for any of the three given the other two, plus power dissipation (P = V × I = I²R = V²/R).
- How do I combine resistors or capacitors in series and parallel?
- Resistors in series add; in parallel, conductances add (1/R_total = Σ 1/R_i). Capacitors are the opposite — in parallel they add; in series, capacitances combine reciprocally. The Resistors and Capacitors series-parallel calculators handle arbitrary N-component networks.
- What's the RC time constant?
- τ = R × C is the time for an RC circuit's voltage to charge to ~63% (or discharge to ~37%) of its final value. After 5τ the circuit is considered fully settled. RL is the same shape with τ = L / R.