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Is the temperature (as defined by rms velocity of particles) higher for a system that is moving relative to the observer? So for instance if a box of particles is moving relative to the observer, would an observer traveling with the box measure a lower temperature than one with the observer? In that case, could we expect chemical reactions to take place faster from an observer's frame of reference if the flask containing the reactants is moving relative to the observer?

Qmechanic
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scl
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  • it is the root mean square in the rest frame of the system of particles, see http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/temper.html. – anna v Aug 26 '22 at 12:58
  • the part of the questiopn with the observer is confused, needs more thought.https://www.astronomy.ohio-state.edu/pogge.1/Ast162/Unit5/gps.html read the special relativity and the clock corrections. . – anna v Aug 26 '22 at 14:54
  • I forgot about time dilation… that would make the reactants appear to move slower to a stationary observer right? So would that imply that the temperature is lower to that observer? – scl Aug 27 '22 at 13:42
  • I am not sure. For example water boils at 100C in the rest frame at one atmosphere pressure. How would a stationary observer of a moving earth "measure" the statistical temperature? He would see the water boil and know it was 100C in the rest frame of the moving earth. – anna v Aug 27 '22 at 19:25

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By changing the frame of reference you are changing the velocity of the centre of mass of the system of particles but not the distribution of velocities relative to the centre of mass of the system which relates to the temperature of the system.

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The key to the rate of reaction is the temperature of the reactance which stays the same being independent of the reference frame as explained above.
When the centre of mass is moving the relative velocities between the reacting molecules does not change and so the rate of reaction does not change. Thus a rate of reaction on a moving train is the same as that on the ground.

Farcher
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  • Too bad !!! But , at least, the reaction products arrive faster to destination ;-) – magma Aug 27 '22 at 09:30
  • Wait but i forgot there’s time dilation, right? So actually shouldn’t the particles should appear to be going slower? (Even relative to each other)… so by that logic the reaction should appear to happen slower, implying that the temperature is lower? – scl Aug 27 '22 at 13:40