A strain gauge forms one arm of the bridge shown in the figure below and has a nominal resistance without any load as $R_s = 300$ . Other bridge resistances are $R_1 = R_2 = R_3 = 300$ . The maximum permissible current through the strain gauge is $20\:mA$. During certain measurement when the bridge is excited by maximum permissible voltage and the strain gauge resistance is increased by $1\%$ over the nominal value, the output voltage $V_0$ in $mV$ is
Voltage, Vin = (300+300)*20m
= 12v
Now, V 0 = 6-((300/603)*12)
= 0.03v. I.e., 30mV
Gatecse