Free · Physics models
Sinusoidal Load Power Factor
Relate real, reactive and apparent power to current, resistance and reactance in a sinusoidal load.
- Formula & worked example
- Private in your browser
- No signup
Calculator inputs
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How to use this calculator
- Enter the known values in the units shown. Results update as you type.
- Where results are editable, change one to solve backwards. Lock a value to hold it fixed.
- Use the worked example to check the method. Reset restores the starting fields.
Private by default
Inputs and results stay in this browser tab. Bookify does not upload or store the values you enter.
Formula and method
Impedance (Z) = 5.0000000; True power (P) = 3.0000000; Reactive power (Q) = 4.0000000. The worked example lists its inputs and unit conventions.
P = I²R; Q = I²X; S = I²√(R²+X²); PF = P/S.
Worked example
Enter these known values and leave the other values blank.
- Current (I)
- 1 A
- Resistance (R)
- 3 Ω
- Reactance (X)
- 4 Ω
- True power (P)
- 3 W
- Reactive power (Q)
- 4 VAR
- Apparent power (S)
- 5 VA
- Phase angle
- 53.13 deg
- Power factor
- 0.6
- Impedance (Z)
- 5 Ω
Assumptions and limitations
- This branch uses nonnegative resistance and reactance magnitudes. It cannot identify inductive versus capacitive phase signs or harmonic distortion. Inverse phase is the principal magnitude.
- Clear the quantity to solve an inverse; keep known quantities fixed with locks. Some inverses are singular or ambiguous and require further known values.
- Unit selectors convert the same physical quantity. Rounded reference constants and presets limit physical accuracy even when arithmetic displays more digits.
Common questions
What does this model assume?
This branch uses nonnegative resistance and reactance magnitudes. It cannot identify inductive versus capacitive phase signs or harmonic distortion. Inverse phase is the principal magnitude.
Can I solve for an input?
Editable calculated fields support the captured inverse relationships. Clear the unknown and supply enough independent known values; an inverse must remain within the declared physical domain.
References
Enforce the reviewed model domain: Power factor must lie between zero and one. Current must be positive for this load branch. Resistance must be nonnegative. This branch requires a nonnegative reactance magnitude. Phase magnitude must lie between zero and 90 degrees.