Conversion for elongation

Elongation is the change in length Dl of a material in relation to its original length l0.
Elongation is caused, for example, by the effect of temperature or force or by physical effects such as magnetostriction or piezoelectricity. The connection between elongation and its cause is described by material coefficients, e.g. thermal expansion coefficient, elastic modulus, magnetostriction or piezo modulus.

Elongation can have different amounts or different signs in different directions,
because the material constants have different values ​​for different directions or because the cause acts in a certain direction.

The unit of elongation is meters per meter.

In technology, elongation is usually given in micrometers per meter (µm/m). Many strains are in this order of magnitude, e.g.
the thermal strain of metal (10...20 µm/m per Kelvin temperature change) or the elastic strain of machine parts (0.1...1000 µm/m).

1 µm/m can also be written (by "abbreviating" the unit) as 10-6 or 1 part per million (ppm) or 0.001 per mille or 0.0001 percent.

In the Anglo-American area, the terms "microepsilon" and "microstrain" are common. A microepsilon (µe) is the same as 1 micrometer per meter (µm/m).

Many physical quantities are determined indirectly by measuring the strain. Think of the countless scales in technology, in commerce and in households, of pressure sensors, force sensors, acceleration sensors, torque sensors...

The strain gauge is used to convert the strain into an electrical signal.

A bridge circuit is always used.