Resistance (Pouillet's Law)

The Pouillet's Law Resistance calculator use Pouilet's Law (R = ρ • L/A) to compute resistance of an object with uniform cross-section and materials based on resistivity of material, length and cross-sectional area of the resistive material.

INSTRUCTIONS:  Choose units and enter the following:

• (A) Cross-section Area  
• (L) Length
• (ρ) Resistivity (units: ohm-meters (Ω⋅m) )

Resistance (R): The resistance is returned in ohms. However, this can be automatically converted to compatible units via the pull-down menu.

Resistivity and Conductivity

When cross-section area and physical composition of material are consistent (uniform), which is an ideal case, the resistivity of a material is an intrinsic property of a material.  Many conductors and resistors are manufactured with uniform materials and cross-sections making a useful application of the concept of resistivity.  This relationship between resistivity and resistance is described in Pouilet's Law for Resistivity in the following formula:

ρ = R • A/L

where:

• ρ = resistivity
• R = electrical resistance
• A = cross-section area
• L = length

Pouilet's Law is named after physicist Claud Pouillet (born 16 Feb 1790, died 14 Jun 1868 , a member of the French Academy of Sciences.