Question

In a mercury thermometer, the ice point is marked as ${10}^o$ and the steam point is marked as ${130}^o$. At ${40}^{o}C$ temperature, what will this thermometer read (in degrees)?

• A. $78$
  
• B. $66$
  
• C. $62$
  
• D. $58$
  

Answer 1

The correct option is D $58$

$\frac{steampoint-icepoint}{giventemp.-icepoint}=constant\frac{100-0}{40-0}=\frac{130-10}{x-10}\Rightarrow \frac{10}{4}=\frac{120}{x-10}\Rightarrow x-10=48\Rightarrow x=58℃$