RL Series Impedance
Compute RL series impedance |Z| and reactance XL from R, L (mH) and frequency f.
Inputs
Formula
Fundamentals
Compute RL series impedance |Z| and reactance XL from R, L (mH) and frequency f.
This tool computes RL Series Impedance from the formula: |Z| = √(R²+XL²), XL = 2πfL
History
Design theory of gears, threads and bearings matured with machine tools and standardisation (AGMA, ISO) since the Industrial Revolution.
Engineering applications
Used for transmission design, joint strength checks and component selection.
Glossary
| Resistance R | Input parameter |
| Inductance L | Input parameter |
| Frequency f | Input parameter |
| Reactance XL | Output result |
| Impedance |Z| | Output result |
How to use
- Fill in Resistance R, Inductance L, Frequency f in the Inputs section (watch the unit on each field).
- Click Calculate; the tool evaluates the formula shown above.
- Read Reactance XL, Impedance |Z| in the results area.
Formula · Worked Example · Knowledge
Formula
核心计算关系：|Z| = √(R²+XL²), XL = 2πfL
输入变量：
- Resistance R
R— Ω - Inductance L
L— mH - Frequency f
f— Hz
输出结果：
- Reactance XL
XL— Ω - Impedance |Z|
Z— Ω
假设/适用：Gearing/thread formulas assume standard, zero-backlash mounting; include error & load factors K_A.
Worked Example
根据公式 |Z| = √(R²+XL²), XL = 2πfL，取 Resistance R = 50 Ω；Inductance L = 100 mH；Frequency f = 50 Hz。
代入计算得：Reactance XL = 31.42 Ω；Impedance |Z| = 59.05 Ω。
Key Points
- Gearing/thread formulas assume standard, zero-backlash mounting; include error & load factors K_A.
- Compare stress with allowable stress and keep a safety factor (≥1.5, ≥2 for critical parts).
- For high speed/load also check lubrication, heat and fatigue life, not just static strength.
Parameters
Inputs
| Parameter | Symbol | Unit | Default |
|---|---|---|---|
| Resistance R (Ω) | R | Ω | 50 |
| Inductance L (mH) | L | mH | 100 |
| Frequency f (Hz) | f | Hz | 50 |
Outputs
| Result | Symbol | Unit |
|---|---|---|
| Reactance XL | XL | Ω |
| Impedance |Z| | Z | Ω |
Applications
- Common engineering use cases