Question

A faulty thermometer reads $5^{\circ }C$ in melting ice and ${99}^{\circ }C$ in dry steam. Find the correct temperature in Fahrenheit scale if this faulty thermometer reads ${52}^{\circ }C$ .

• A. ${84}^{\circ }F$
• B. ${122}^{\circ }F$
• C. ${56}^{\circ }F$
• D. ${88}^{\circ }F$

Answer 1

Answer: (B)

${122}^{\circ }F$

If a thermometer is wrong calibrated then,
If $X$ the temperature reading on the faulty thermometer scale then,
$t=\frac{(X-LFP)}{(UFP-LFP)}\times 100$. Where, $t=$actual reading.

Now, it reads ${99}^{\circ }C\left(UFP\right)$ in dry steam and $5^{o}C\left(LFP\right)$. So, using formula we can get the actual temperature for ${50}^{\circ }C$

Using, $\frac{C}{5}=\frac{F-32}{9}$

reading is actually ${50}^{\circ }C={122}^{\circ }F$.