A thermocouple has an e$.$m$.$f$.$ of $4\mathrm{.}1$ mV at $100$C and $16\mathrm{.}4$ mV at $400$C relative to a cold junction

of $0$C$.$ A deflection bridge incorporating a nickel metal resistance sensor will be used as the

voltage source ET$2,0$ necessary for automatic reference compensation of the thermocouple e$.$m$.$f$.$

The nickel sensor has a resistance of $10$ at $0$C and a temperature coefficient of resistance of $6\mathrm{.}8$

$103$

$$C$1$

$.$ Design the deflection bridge assuming a $1$ V supply is available. It is given that the

thermocouple e$.$m$.$f$.$ ET$2,0$ is expressed as: a$1$t$2+$ a$2$t$2^2+...$

The above relation may be approximated to a first$-$order relationship as T$2,$ the reference junction

temperature, is small.