Question

The pressure of air in the bulb of a constant volume gas thermometer at $0^{\circ }$C and ${100}^{\circ }$C are 73.00 cm and 100 cm of mercury respectively. Calculate the pressure at room temperature ${20}^{\circ }$C.

• A. $78.4cm$ of Hg
• B. $88.4cm$ of Hg
• C. $98.4cm$ of Hg
• D. $108.4cm$ of Hg

Answer 1

The correct option is A $78.4cm$ of Hg

$t=\frac{P_t-P_0}{P_{100}-P_0}\times {100}^{\circ }C$
$\%$ increase in pressure from $P_0$
${20}^{\circ }C=\frac{P_t-73}{100-73}\times 100$
$=78.4cm$ of Hg