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Temperature is a measure of the average kinetic energy of all the molecules in a gas. As the temperature and, therefore, kinetic energy, of a gas changes, the RMS speed of the gas molecules also changes. The RMS speed of the molecules is the square root of the average of each individual velocity squared.
The kinetic theory of gases is a historically significant, but simple, model of the thermodynamic behavior of gases, with which many principal concepts of thermodynamics were established. The model describes a gas as a large number of identical submicroscopic particles (atoms or molecules), all of which are in constant, rapid, random motion. Their size is assumed to be much smaller than the average distance between the particles. The particles undergo random elastic collisions between themselves and with the enclosing walls of the container. The basic version of the model describes the ideal gas, and considers no other interactions between the particles and, thus, the nature of kinetic energy transfers during collisions is strictly thermal.
For some systems- far from equilibrium- the temperatures can be different- or even negative.
How is the temperature measured before reaching equilibrium?
Do their angular speeds affect the masure of the system's temperature?
You can measure the temperature of your system of a box of metal balls floating in space by filling the box with water.Viscous drag will slow the balls down and warm the water up.
That would convert mechanical kinetic energy into thermal energy.
It means that the end temperature is different than initial temperature, which is the one we want to determine.
Quote from: hamdani yusuf on 20/09/2020 14:39:33That would convert mechanical kinetic energy into thermal energy.Is there a difference?Quote from: hamdani yusuf on 20/09/2020 14:39:33It means that the end temperature is different than initial temperature, which is the one we want to determine.So, it is exactly the same as the experiment to measure the temperature of a flame,
Quote from: Bored chemist on 20/09/2020 15:11:14Quote from: hamdani yusuf on 20/09/2020 14:39:33That would convert mechanical kinetic energy into thermal energy.Is there a difference?Quote from: hamdani yusuf on 20/09/2020 14:39:33It means that the end temperature is different than initial temperature, which is the one we want to determine.So, it is exactly the same as the experiment to measure the temperature of a flame, an object with high mechanical energy but low thermal energy is cool. an object with low mechanical energy but high thermal energy is hot.
In a more realistic scenario, the spheres wouldn't be stationary in their box- the uncertainty principle forbids it- so, from time to time they would bump into each other and they would convert rotational energy into translational and vibrational energy.After a while, they would reach equilibrium where, on average, their energy is divided equally among all the available degrees of freedom.And that's a temperature.
You can have a system with more than one temperature.
It only means that in case of gases, they contribute less than translation.
But their atomic mass are very different, (4 for Helium and 222 for Radon)Their densities also vary significantly (0.1786 g/L for Helium and 9.73 g/L for Radon).