For a copper-iron (Cu-Fe) couple,the thermo e | vedclass

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(A) The thermo $e.m.f.$ $E$ in a thermocouple is given by the relation $E = \alpha	heta + \frac{1}{2}\beta	heta^2$,where $	heta$ is the temperature

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$350\,^{\circ}C$

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(A) The thermo $e.m.f.$ $E$ in a thermocouple is given by the relation $E = \alpha	heta + \frac{1}{2}\beta	heta^2$,where $	heta$ is the temperature of the hot junction in $^{\circ}C$ and the cold junction is at $0\,^{\circ}C$.Comparing the given equation $E = 14	heta - 0.02	heta^2$ with the standard form,we get $\alpha = 14$ and $\frac{1}{2}\beta = -0.02$.Thus,$\beta = -0.04$.The neutral temperature $	heta_n$ is the temperature at which the thermo $e.m.f.$ is maximum,which occurs when $\frac{dE}{d	heta} = 0$.$\frac{dE}{d	heta} = 14 - 0.04	heta = 0$.Solving for $	heta$,we get $	heta_n = \frac{14}{0.04} = 350\,^{\circ}C$.

For a copper-iron $(Cu-Fe)$ couple,the thermo $e.m.f.$ (temperature of cold junction $= 0\,^{\circ}C$) is given by $E = (14\theta - 0.02\theta^2)\,\mu V$. The neutral temperature will be

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