science, absolute zero
posted by minerva .
what is absolute zero? if 0 kelvin is the lowest temperature we can ever get, then does it mean that -273 degree Celsius is the lowest temperature we can reach? the book said "when we remove all of the energy from something, its temperature will be zero kelvin", what does energy have to do with temperature?
Absolute zero is, indeed, 0 Kelvin and that is equal to -273.16o Celsius. AND we would have absolute zero IF we removed all of the energy. That has never been done but scientists have come close. The last article I read said we had come within a few picodegrees (1 pd = 1 x 10-12 degrees) of absolute zero but that article was a few years ago. Perhaps it is different now. Finally, what does energy have to do with temprature. Only everything. The kinetic energy of a molecule or atom = 1/2 mv2 where m is mass and v is velocity. Velocity, in turn, is determined by the temperature. Higher temperatures makes the molecule or atom move faster. Lowering the temperature makes them move slower. At absolute zero all motion stops for the energy is zero. Theoretically we will never reach absolute zero. I hope this helps clear things for you.
i got the part about how energy has to do with temperature. but if 0 kelvin is -273 degree celsius, then that's the lowest temperature we can get? i mean, i know the book said 0 kelvin is the lowest temperature, and i know that 0 kelvin is approximately -273 degree celsius, but surely there are temperatures lower than -273 degree celsius?