Question

The junctions of $Ni-Cu$ thermocouple are at $0C$ and $100C$. The seebeck e.m.f. developed in the thermocouple will be (given a) $Ni-Cu=16.3\times {10}^{6}V/C$and b) $N{i}_{C}u=-0.042V/C2$)

• A. $1.42\times {10}^{3}V$
• B. $1.42\times {10}^{-3}V$
• C. $1.42\times {10}^{4}V$
• D. $1.42\times {10}^{-4}V$

Answer 1

Answer: (B)

$1.42\times {10}^{-3}V$

given $a(Ni-cu)=16.3\times {10}^{-6}V/C$and $b\left(Nicu\right)=-0.042V/C^2)$
The Seebeck e.m.f. developed in the thermocouple.
$E_{Ni-cu}=aT+\frac{b}{2}{T}^2$
$=(16.3\times {10}^{-6})\times 100-(0.042\times {10}^{-6}){100}^2$
$\therefore E_{Ni-cu}=(16.3\times {10}^{-4})-2.1\times {10}^{-4}$
$=14.2\times {10}^{-4}$
$=1.42\times {10}^{-3}V$