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Question
The pressures of the gas in a constant volume gas thermometer are 80 cm, 90 cm and 100 cm of mercury at the ice point, the steam point and in a heated wax bath, respectively. Find the temperature of the wax bath.
Solution
Given:
In a constant volume gas thermometer,
Pressure of the gas at the ice point, P0 = 80 cm of Hg
Pressure of the gas at the steam point, P100 = 90 cm of Hg
Pressure of the gas in a heated wax bath, P = 100 cm of Hg
The temperature of the wax bath
\[\left( T \right)\] is given by:
\[T = \frac{P - P_0}{P_{100} - P_0} \times 100°C\]
\[ \Rightarrow T = \frac{100 - 80}{90 - 80} \times 100\]
\[ \Rightarrow T = \frac{20}{10} \times 100\]
\[ \Rightarrow T = 200° C\]
Therefore, the temperature of the wax bath is 200o C.
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