How it works
Use direct current power with the units stated beside the fields. This form solves for current magnitude; enter the known quantities in Power magnitude, Voltage magnitude.
Inputs and units
| Input | Example value | What to enter |
|---|---|---|
| Power magnitude | 45 W | Formula symbol: P. Required unit: W. Must be greater than zero. |
| Voltage magnitude | 9 V | Formula symbol: U. Required unit: V. Must be greater than zero. |
Worked example
Show example inputs and results
This example is generated by the same calculation engine using the starting values in the form. Your own inputs produce your own result.
- Power magnitude
- 45 W
- Voltage magnitude
- 9 V
Complete example results
- Current magnitude
- 5 A
Reading the result
The result solves for current magnitude from the entered quantities. Check the result unit and the formula conditions before using it.
Questions and answers
Can I use the example values for my own calculation?
The example values illustrate the calculation. Replace every input with your own information, especially dates, rates and the selected operation.
When can I use the current magnitude result?
This model uses positive magnitudes. Use steady DC magnitudes. AC phase, power factor and harmonics are excluded.
Why are some results rounded?
Results display up to 8 decimal places. Calculations use the unrounded values; very small values use scientific notation. JavaScript floating-point arithmetic can introduce tiny rounding differences.
Are my inputs sent to a server?
The calculator processes inputs in your browser. Its code does not send your values to a server.
Method sources: openstax.org