A constant volume gas thermometer shows pressure readings of $P_1$ at the triple point of water and $P_2$ at the boiling point of water at 1 atm. What is the ideal gas temperature corresponding to a pressure reading of $2P_1$?

Very low temperatures are measured by

Mercury boils at ${367^0}C$. However, mercury thermometers are made such that they can measure temperature up to ${500^0}C$. This is done by

Very low temperatures are measured by

A platinum resistance thermometer reads ${0^0}C$ when its resistance is 80 $\Omega$ and ${100^0}C$ when its resistance is 90$\Omega$. Find the temperature at the platinum scale at which the resistance is 86$\Omega$

Which of the following properties of materials is NOT utilized in temperature measurement devices?