Phasor Real Part (Polar → Rect)
R = |Z| · cos(θ)
Quick answer
This calculator solves R = |Z| × cos(θ) for Real Part. With Magnitude 1.03 kΩ, Phase Angle 45 °, the result is 0.7283 kΩ. It solves in 2 directions, so you can enter the values you have and get the one you need.
Calculator
Formula
Description
Converting a phasor from polar to rectangular form, the real (in-phase) component is the magnitude times the cosine of the phase angle. This is the resistive part of an impedance or the in-phase part of a voltage or current, and it is what determines real power dissipation. It is the projection of the phasor onto the real axis.
Variables
- R — Real / in-phase component (Ω)
- |Z| — Phasor magnitude (Ω)
- θ — Phase angle (degrees)
Practical Notes
The imaginary part is X = |Z|·sin(θ). For power, the real component of current times voltage gives true (watt) power; the imaginary gives reactive (VAR) power.
Symbols and units
| Symbol | Meaning | Default unit | Accepted units |
|---|---|---|---|
| R | Real Part | Ω | mΩ, Ω, kΩ, MΩ |
| mag | Magnitude | Ω | mΩ, Ω, kΩ, MΩ |
| theta | Phase Angle | ° | ° |
Step by step
- 1. What you know: Magnitude 1.03 kΩ, Phase Angle 45 °
- 2. The relation: R = |Z| × cos(θ)
- 3. Substitute: mag = 1.03 kΩ, theta = 45 °
- 4. Result: Real Part = 0.7283 kΩ
Nearest standard component values
| Series | Nearest value | Error |
|---|---|---|
| E12 | 0.68 kΩ | 6.6% |
| E24 | 0.75 kΩ | 3% |
Worked examples
Minimum range
Given: Magnitude 2.2 Ω, Phase Angle 1.5 °
Result: Real Part = 2.199 Ω
Low range
Given: Magnitude 22 Ω, Phase Angle 15 °
Result: Real Part = 21.25 Ω
Typical
Given: Magnitude 1.03 kΩ, Phase Angle 45 °
Result: Real Part = 0.7283 kΩ
High range
Given: Magnitude 10.3 kΩ, Phase Angle 75 °
Result: Real Part = 2.666 kΩ
Maximum range
Given: Magnitude 103 kΩ, Phase Angle 750 °
Result: Real Part = 89.2 kΩ
Solving for each variable
Solve for Real Part
Magnitude 2.2 Ω, Phase Angle 1.5 ° → 2.199 Ω
Solve for Magnitude
Real Part 1 Ω, Phase Angle 1.5 ° → 1 Ω
How Real Part changes with Magnitude
| Magnitude (input) | Real Part (result) |
|---|---|
| 103 Ω | 72.83 Ω |
| 0.2575 kΩ | 0.1821 kΩ |
| 0.515 kΩ | 0.3642 kΩ |
| 0.7725 kΩ | 0.5462 kΩ |
| 1.03 kΩ | 0.7283 kΩ |
| 1.545 kΩ | 1.092 kΩ |
| 2.06 kΩ | 1.457 kΩ |
| 4.12 kΩ | 2.913 kΩ |
| 7.21 kΩ | 5.098 kΩ |
| 10.3 kΩ | 7.283 kΩ |
The same result in other units
| Unit | Value |
|---|---|
| mΩ | 728300 |
| Ω | 728.3 |
| kΩ | 0.7283 |
| MΩ | 0.0007283 |
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<p><a href="https://vbatpower.com/formulas/polar-to-rect-real/">Phasor Real Part (Polar → Rect)</a> Calculator by vbatpower.com</p> Frequently asked questions
How do you calculate Phasor Real Part (Polar → Rect)?
Use R = |Z| × cos(θ). With Magnitude 1.03 kΩ, Phase Angle 45 °, Real Part works out to 0.7283 kΩ.
What is the formula for Phasor Real Part (Polar → Rect)?
The formula is R = |Z| × cos(θ). Converting a phasor from polar to rectangular form, the real (in-phase) component is the magnitude times the cosine of the phase angle.
How do you find Magnitude when you know the other values?
Rearrange for Magnitude: with Real Part 1 Ω, Phase Angle 1.5 °, Magnitude is 1 Ω.
What units does Phasor Real Part (Polar → Rect) use?
Real Part is shown in mΩ, Ω, kΩ, MΩ. Values are held in SI base units internally, so you can mix prefixes without converting by hand.
Related Concepts
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