Inductance Calculator Formula
Understand the math behind the inductance calculator. Each variable explained with a worked example.
Formulas Used
Inductance
inductance = 4e-7 * pi * pow(turns, 2) * area / sol_lengthInductance (mH)
inductance_mh = 4e-7 * pi * pow(turns, 2) * area / sol_length * 1000Variables
| Variable | Description | Default |
|---|---|---|
turns | Number of Turns | 100 |
area | Cross-Sectional Area(m²) | 0.001 |
sol_length | Solenoid Length(m) | 0.1 |
How It Works
Solenoid Inductance
Inductance quantifies the ability of a coil to store energy in a magnetic field.
Formula
L = mu_0 * N² * A / l
where N is the number of turns, A is the cross-sectional area, and l is the solenoid length.
Worked Example
A solenoid with 100 turns, area 0.001 m², length 0.1 m.
- 01L = mu_0 * N² * A / l
- 02L = 4*pi*1e-7 * 10000 * 0.001 / 0.1
- 03L = 1.2566e-3 * 0.01
- 04L = 1.2566e-5 H = 0.1257 mH
Frequently Asked Questions
What is inductance?
Inductance is the property of a conductor that opposes changes in current. A changing current through an inductor induces a voltage that resists the change.
How does a ferrite core affect inductance?
A ferrite core increases the effective permeability (mu = mu_r * mu_0), multiplying the inductance by the relative permeability mu_r of the core material.
What is the unit of inductance?
The henry (H), named after Joseph Henry. One henry means a current change of 1 A/s induces 1 volt.
Ready to run the numbers?
Open Inductance Calculator