Question #ddcfa
1 Answer
Because the temperature is a measure of motion energy. When motion stops, so is the temperature.
Explanation:
When something moves, it has kinetic energy. All substance is made up of atoms or molecules. Molecules do move: they vibrate, tumble or goes from place to place.
We don't measure the kinetic energy of individual molecules and tally their total energies directly because it is humanly impossible. Instead we measure their collective energy in the form of temperature. If molecules have motion energy, they have temperature.
If molecules cease their motions (translation, rotation and vibration) completely, the temperature becomes zero (Kelvin). Therefore, it is not the temperature that make them cease the motion, it's ceasing their motions that lower their temperature..until the absolute zero.
Quantum mechanics, however, does allow motions (vibration) at zero temperature. So it is not completely true that motion ceases completely at zero temperature.
