Home / Aptitude Tests / Physics / The lower and upper ...

The lower and upper fixed points marked on a Mercury-in-g...

The lower and upper fixed points marked on a Mercury-in-glass thermometer are 210mm apart. The end of the mercury column in the tube is 49mm above the lower fixed point in a room. What is the temperature of the room in degrees Celsius? 

A.

55.3\(^o\)C

B.

23.3\(^o\)C

C.

49.0\(^o\)C

D.

16.43\(^o\)C

Correct answer is B

\(\frac{49 - 0}{210 - 0}\) = \(\frac{\theta - 0}{100 - \theta}\) 

\(\frac{49}{210} = \frac{\theta}{100}\) 

49 x 100 = 210 x \(\theta\) 

\(\theta = \frac{4900}{210}\) = 23.3\(^o\)