8.16  Note that this solutions uses notation from the text, which differs  very slightly from some of the lecture notes regarding uncertainty.

 

Vs = 2V 0.2%

V0 = 12.5 mV 0.3%

S = 2.09 0.5%

R2 = 120 W 0.1%

R3i = 120 W 0.15%

 

We can use Eq. 8.22 to estimate the strain:

To obtain the uncertainty we will use Eq. 7.4. To use this, we need the partial derivatives with respect to each of the independent variables:

wR3i = 1200.0015 = 0.18W

wR2 = 1200.001 = 0.12W

wS = 2.090.005 = 0.0105

wVs = 20.002 = 0.004 V

wV0 = 12.510-30.003 = 0.0000375 V