Question

The resistance of platinum wire is 2.4 ohms at $0^{o}C$ and 3.4 ohms at ${100}^{o}C$. lf the resistance at $t^{o}C$ is 4 ohms then the temperature t is equal to

• A. ${160}^{O}C$
• B. ${140}^{o}C$
• C. ${180}^{o}C$
• D. ${120}^{o}C$

Answer 1

Answer: (A)

${160}^{O}C$

$t=\frac{R_t-R_0}{R_{100}-R_0}\times 100=\frac{4-2.4}{3.4-2.4}\times 100=\frac{1.6}{1}\times 100$
$={160}^{0}C$