Question
Find the thermo-emf developed in a copper-silver thermocouple when the junctions are kept at 0°C and 40°C. Use the data in table.
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Answer
$\text{E}=\text{a}_{\text{AB}}\theta+\text{b}_{\text{AB}}\theta^2$
$\text{a}_{\text{CuAg}}=\text{a}_{\text{CuPb}}-\text{b}_{\text{AgPb}}$
$=2.76-2.5=0.26\mu\text{v}/^\circ\text{C}$
$\text{b}_{\text{CuAg}}=\text{b}_{\text{CuPb}}-\text{b}_{\text{AgPb}}$
$=0.012-0.012\mu\text{vc}=0$
$\text{E}=\text{a}_{\text{AB}}\theta=(0.26\times40)\mu\text{V}$
$=1.04\times10^{-5}\text{V}$
$\text{a}_{\text{CuAg}}=\text{a}_{\text{CuPb}}-\text{b}_{\text{AgPb}}$
$=2.76-2.5=0.26\mu\text{v}/^\circ\text{C}$
$\text{b}_{\text{CuAg}}=\text{b}_{\text{CuPb}}-\text{b}_{\text{AgPb}}$
$=0.012-0.012\mu\text{vc}=0$
$\text{E}=\text{a}_{\text{AB}}\theta=(0.26\times40)\mu\text{V}$
$=1.04\times10^{-5}\text{V}$
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