A null-type Wheatstone bridge is used to accurately measure the resistance of a strain gauge during a calibration procedure. The circuit shown in Fig. 6.1 is used, in which the known fixed resistance...

A null-type Wheatstone bridge is used to accurately measure the resistance of a strain

gauge during a calibration procedure. The circuit shown in Fig. 6.1 is used, in which

the known fixed resistance values are given by R2 ¼ 331.2 U and R3 ¼ 327.5 U. The

thermometer is inserted in the circuit as Ru and then the variable resistance box Rv is

adjusted until the bridge output voltage Vo goes to zero. At this balance point, the

value of Rv is 352.5 U. Calculate the resistance of the strain gauge.