Electric Current Density Calculator
Compute current density J = I/A, drift velocity and resistance per length.
Input Data
Current A
A
Cross Section Area M2
m²
Carrier Density Per M3
1/m³
Charge C
C
Resistivity Ohm M
Ω·m
Results
J = I/A.
1,000,000A/m²
v_d = I/(nAq).
0.0000734376m/s
ρ/A.
0.0168Ω/m
At a glance:J = I/A; v_d = I/(nAq); R' = ρ/A. Complements current and drift-velocity.
Formula
J = I / A.
v_d = I/(n·A·q).
$$J = \frac{I}{A} = nqv_d, \quad v_d = \frac{J}{nq} = \frac{I}{nqA}, \quad \frac{R}{L} = \frac{\rho}{A}$$How to Use
- Enter current, area and (optional) carrier density/resistivity.
- The tool returns J, drift and R'.
Case Studies
I=1, A=1e-6, n=8.5e28
J=1e6 A/m², v_d≈7.3e-5 m/s.
FAQ
Drift speed small?
Yes — electrons drift slowly; signal speed is near light speed.
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References
Content review: Calculatorism Science Team. Results are for reference only; please refer to the relevant authorities for the official figures.