🎓 Engineering • Electrical Engineering
100% Client-Side Privacy
Inductor Calculator (Energy & RL Time Constant)
Calculates magnetic energy stored in inductors and RL circuit transient response time constants.
Inductor Magnetic Energy & RL Transient Curve
Solves magnetic field energy ($E = \frac12LI^2$), flux linkage, and RL current rise exponential transient
Inductor Application Presets
RL Current Rise Milestones (τ = L / R = 0.1 ms)
5τ Steady-State = 0.5 ms1τ (63.2%)0.948 A0.1 ms
2τ (86.5%)1.297 A0.2 ms
3τ (95.0%)1.425 A0.3 ms
4τ (98.2%)1.473 A0.4 ms
5τ (99.3%)1.49 A0.5 ms
Stored Magnetic Energy
11.25 mJ
E = ½ L I²Magnetic Flux Linkage
15 mWb
λ = L × IRL Time Constant (τ)
0.1 ms
τ = L / RWhat is an Inductor?
An inductor is a passive electronic component that opposes changes in electric current by storing energy in its surrounding magnetic field according to Faraday’s law of induction.
Formula & Step-by-Step Calculation
E = ½ · L · I², τ = L / R, V_L = L · (di / dt)
Magnetic energy storage and RL circuit exponential time constant.
Worked Step-by-Step Examples
Example 1
A 10mH inductor carries 1.5A in a circuit with 100Ω resistance
Solution: Energy: 11.25 mJ, Time Constant τ = 0.100 ms
• E = 0.5 × 0.010 H × (1.5)² = 0.01125 J = 11.25 mJ; τ = 0.010 / 100 = 0.0001 s = 0.1 ms
Common Real-World & Academic Use Cases
- ✓ Switch-mode buck/boost converter inductor sizing
- ✓ Flyback diode suppression for relay coils
- ✓ Audio crossover passive low-pass filter design
How to Use the Inductor Calculator (Energy & RL Time Constant)
1
Enter Inductance (mH)
Specify inductance value.
2
Enter Current & Resistance
Input circuit current (A) and resistance (Ω).
3
Read Energy & τ
Review stored magnetic energy and decay time constant.
Frequently Asked Questions
Q: Why can current through an inductor not change instantaneously?
Because an instantaneous change in current would require infinite voltage across the inductor (V = L·di/dt).