Gauge factor

Gauge factor (GF) or strain factor of a strain gauge is the ratio of relative change in electrical resistance R, to the mechanical strain ε. The gauge factor is defined as:^[1]

GF={\frac {\Delta R/R}{\Delta L/L}}={\frac {\Delta R/R}{\varepsilon }}=1+2\nu +{\frac {\Delta \rho /\rho }{\varepsilon }}

where

ε = strain = $\Delta L/L_{0}$ $\Delta L/L_{0}$
- $\Delta L$ = absolute change in length
- $L_{0}$ = original length
ν = Poisson's ratio
ρ = resistivity
ΔR = change in strain gauge resistance due axial strain and lateral strain
R = unstrained resistance of strain gauge

^ Beckwith, Thomas G., N. Lewis Buck, Roy D. Marangoni (1982). Mechanical Measurements (Third ed.). Reading, MA: Addison-Wesley Publishing Co. p. 360. ISBN 0-201-00036-9.{{cite book}}: CS1 maint: multiple names: authors list (link)