Module 4 : THERMOELECTRICITY
Lecture 21 : Seebeck Effect
Example
  Seebeck voltage for Copper- Constantan (Cn) thermocouple is given by the linear relation $V= a+bT$, where $T$ is the absolute temperature of the hot junction and $a$ and $b$ are constants given by
Cu : $ a= 0.6$ mV                               $ b = 0.008$ mV/K
Cn : $ a= -20$ mV                            $ b = -0.056$ mV/K
  Calculate the thermoelectric power when the hot junction is at 100 $^\circ$C.
  Solution
 
\begin{eqnarray*} V_{Cu-Cn} &=& (a+bT)_{Cu}-(a+bT)_{Cn}\\ &=& 0.6 + 0.008T + 20 + 0.056 T\\ &=& 20.6 + 0.064 T \end{eqnarray*}
  The thermoelectric power
 
\begin{displaymath}\alpha = \frac{dV}{dT} = 0.064 \ \ {\rm mV/K}\end{displaymath}

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