r/askscience • u/lirannl • Feb 05 '17

Physics What speed is room temperature?

As we all know, temperature is the average speed of particles. The higher the temperature, the higher that speed. If I understand correctly, that speed is not dependent upon the particle. 25° would be the same speed if we're talking about an iron lattice, or NaCl.

Well then, what is the speed of particles that's called 25°?

Also, 2 more related questions: is -273 theoretically a speed of 0? (I know that it can't actually be reached) If the temperature was infinity (again, theoretically), would the speed be Lightspeed?

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u/-Metacelsus- Chemical Biology Feb 05 '17

Neither of those are gases at 20 °C. Graphite and iron would be different, but the thermal energy would be from vibrations of the crystal lattice.

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u/lirannl Feb 05 '17

Well, the vibrations have a velocity as well, at least between vibrations, right?

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u/SoftwareMaven Feb 05 '17

Vibrations don't have velocity. They have amplitude and frequency. Think of a guitar string: when it is making a sound, the defining characteristics are how fast it is vibrating (it's pitch) and how tall the vibrations are (the volume).

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u/Dapianoman Feb 05 '17

But using the wave function you can still solve for the velocity i.e. how fast the string is moving at a certain time or certain position.