
Electrical and electronic principles
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position to compensate for temperature changes. Quite simply, when a strain
gauge is stretched its resistance will increase, and when it is compressed its
resistance decreases.
Most strain gauges consist of a thin layer of lm that is xed to a exible
backing sheet, usually paper. This, in turn, is bonded to the part where strain
is to be measured. The sensitivity of a strain gauge is dened by its ‘gauge
factor’.
where: K = gauge factor; R = original resistance; Δ R = change in resistance;
E = strain (change in length/original length, l/l).
Most resistance strain gauges have a resistance of about 100 and ...