3 ms·
A similar unit exists for electrical resistivity. ρ := Ωm²/m. To calculate the resistance of a specific piece of wire, plug in the intrinsic property of coppe
by pvillano 4y ago
A similar unit exists for electrical resistivity.
ρ := Ωm²/m.
To calculate the resistance of a specific piece of wire, plug in the intrinsic property of copper (resistivity), and the dimensions of the specific wire. Out comes resistance.
Ω(wire) = ρ(copper) × length ÷ area
Where things get weird are thin films, ICs, and pcb traces with constant thicknes.
The unit of sheet resistance is ohms per square.
Because resistance increases with length and decreases with width, multiplying both by the same number doesn't change the resistance. Any square cut from the same sheet of copper has the same resistance between two opposite edges.