Labo Élec
electrical lab simulator
Exercise from the chapter "Ohm's law & resistance"
Level 3 of 5 · Skills: Calculate
What is the resistivity of the metal of a wire with resistance 11.2 Ω, length 2 m and diameter 0.5 mm? (Answer in Ω·mm²/m.)
R = 11.2 Ω · l = 2 m · D = 0.5 mm
Parametric exercise: the values change with every draw; these are one example.
Guided problem in 4 steps: unknown, formula, units, data, result.
S = π·D²/4 = 0.196 mm²; ρ = R·S/l = 11.2 × 0.196 / 2 ≈ 1.1 Ω·mm²/m: it is nichrome.