Question

The resistance of a resistance thermometer has values 2.71 and 3.70 ohm at ${10}^{\circ }Cand{100}^{\circ }C$. The temperature at which the resistance is 3.26 ohm is

• A. ${40}^{\circ }C$
• B. ${50}^{\circ }C$
• C. ${60}^{\circ }C$
• D. ${70}^{\circ }C$

Answer 1

The correct option is B

${50}^{\circ }C$

Change in resistance 3.70 - 2.71 = 0.99 $\Omega$ corresponds to interval of tempetature ${90}^{\circ }C$ .

So change in resistance 3.26 - 2.71 = 055 $\Omega$ corresponds to change in temperature

= $\frac{90}{0.99}\times 0.55={50}^{\circ }C$