About the Ohm's Law Alternative Calculator
What is the Ohm's Law Alternative Calculator?
Resistance depends on what a conductor is made of and its shape. This wire resistance calculator uses the resistivity of copper, aluminium, nichrome and other materials with the length and cross-sectional area.
Apply a voltage to see the current by Ohm's law, the current density and the heat produced.
How to use the Ohm's Law Alternative Calculator
- Material (sample: Copper (1.68 × 10⁻⁸ Ω·m))
- Custom Resistivity (Ω·m) (sample: 0)
- Length (m) (sample: 100)
- Cross-Sectional Area (mm²) (sample: 1)
- Applied Voltage (V) (sample: 12)
- Press Calculate Wire Resistance (results also refresh as you type). The result card shows the Resistance, along with Conductance (1 ÷ R), Current at the voltage (I = V ÷ R), Current density and Power dissipated.
Formula used
R = ρ × L ÷ A
- ρ = resistivity at 20 °C (copper 1.68 × 10⁻⁸ Ω·m)
- Conductance = G = 1 ÷ R, in siemens
- Current = I = V ÷ R
Resistance of metals rises about 0.4% per °C.
Worked example
These are the sample values already filled in the calculator above, and the result it returns for them:
| Input | Sample value |
|---|---|
| Material | Copper (1.68 × 10⁻⁸ Ω·m) |
| Custom Resistivity (Ω·m) | 0 |
| Length (m) | 100 |
| Cross-Sectional Area (mm²) | 1 |
| Applied Voltage (V) | 12 |
| Result | Value |
|---|---|
| Resistance | 1.68 Ω |
| Conductance (1 ÷ R) | 0.59524 S |
| Current at the voltage (I = V ÷ R) | 7.1429 A |
| Current density | 7.1429 A/mm² |
| Power dissipated | 85.714 W |
Tips for using the Ohm's Law Alternative Calculator
- Nichrome's high resistivity makes it ideal for heater elements.
- Doubling a wire's length doubles its resistance; doubling its area halves it.