Tempertaure of a moving object vs. stationary one

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SUMMARY

The discussion clarifies that the temperature of an object is defined by its internal energy, which encompasses molecular motion, rather than its net kinetic energy due to motion in space. Specifically, moving an object does not inherently increase its temperature, as temperature is related to the internal kinetic energy of molecules, not the object's overall kinetic energy. The distinction between internal energy and net kinetic energy is crucial, as it prevents arbitrary temperature values based on different inertial frames. This understanding is vital for accurately interpreting thermodynamic principles.

PREREQUISITES
  • Understanding of kinetic energy, specifically the formula KE = 1/2MV^2
  • Basic knowledge of thermodynamics and internal energy concepts
  • Familiarity with molecular motion and its impact on temperature
  • Awareness of inertial frames of reference in physics
NEXT STEPS
  • Research the principles of thermodynamics, focusing on internal energy versus kinetic energy
  • Study the effects of molecular motion on temperature in various states of matter
  • Explore the implications of relativistic speeds on temperature measurements
  • Investigate the relationship between kinetic energy and thermal energy in different physical systems
USEFUL FOR

Students and professionals in physics, particularly those interested in thermodynamics, molecular dynamics, and the relationship between motion and temperature. This discussion is beneficial for anyone seeking to deepen their understanding of energy concepts in physical systems.

Giga_Man
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Hello.
If temperature is defined by the average kinetic energy of molecules, does this mean that moving an object in space increase it's temperature? (Or, say, looking at it from another inertial frame of reference?).
talking about non-relativistic speeds.

Thanks a lot!
Mike
 
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temperature is the system's *internal* energy, which includes molecular translational, rotational and vibrational motion. it does NOT include the system's *net* kinetic energy, which would be say... a piece of rock moving really fast, as opposed to a piece of rock that's still - the internal motion of the silicon/oxygen/iron/magnesium/carbon that make up the rock, stays the same.

if it were otherwise, things could have arbitrary temperatures, since you can always find a frame that's moving arbitrarily fast (within the speed of light) relative to another.
 
If you put 1J of energy into a piece of rock, you can either move it a bit or warm it up a bit. Same amount of energy but it's much more accessible (to reclaim) when it's non-random motion then when it's 'thermal'. The distinction is so relevant that we give the two forms of energy two different names.
 
I'm a bit of a Novice but the part of Kinetic Energy V^2(KE=1/2MV^2) I have noticed that it is apart of many different equations which means it can be manipulated a lot by different forces which affect the velocity of the object or particle so I'm sure you can increase the velocity without increasing the temperature.
 
EU_Raider said:
I'm a bit of a Novice but the part of Kinetic Energy V^2(KE=1/2MV^2) I have noticed that it is apart of many different equations which means it can be manipulated a lot by different forces which affect the velocity of the object or particle so I'm sure you can increase the velocity without increasing the temperature.

Well, there's an awful lot of really cold stuff hurtling around in space at amazingly high speeds. Massive available energy in the form of KE if it hit us but not enough thermal energy to nudge a thermometer (travelling alongside it).
 

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