Question

A centigrade and a Fahrenheit thermometer are dipped in boiling water. The water temperature is lowered until the Fahrenheit thermometer resisters ${140}^0$. What is the fall in temperature as registered by the Centigrade thermometer?

• A. ${30}^0$
• B. ${40}^0$
• C. ${60}^0$
• D. ${80}^0$

Answer 1

The correct option is B ${40}^0$

The relation between Fahrenheit and centigrade scale is given by,

$C=\frac{5}{9}(F-32)$

Here , $F=140$ so $C=\left(5/9\right)(140-32)=\left(5/9\right)\left(108\right)=60$

Temperature in centigrade scale of boiling water is ${100}^{\circ }C$

So, fall in temperature $=100-60={40}^{\circ }C$