Third option represents the given relation as the principle of calorimeter states that if there is no loss of heat in surrounding the total heat lost by hot body equal to the total heat gained by a cold body .i.e. heat lost = heat gained Principle of Thermal Equilibrium Thermal equilibrium obeys the zeroth law of thermodynamics. A system is said to be in thermal equilibrium with itself if the temperature within the system is spatially and temporally uniform Principle of colours- The principles of colour theory are just like the other design principles we use every day—they are creative tools that can be used to solve visual problems. Principle of vaporisation Vaporisation of an element or compound is a phase transition from the liquid phase to vapour.