## Is there a difference between Thermal energy and Kinetic energy? [ENDORSED]

$\Delta U=q+w$

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### Is there a difference between Thermal energy and Kinetic energy?

If thermal energy is the energy that comes from heat, and heat is the result of the faster movement of a substance's particles, which is ultimately nothing but more kinetic energy in its particles. Then do the two have the same meaning?

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### Re: Is there a difference between Thermal energy and Kinetic energy?  [ENDORSED]

They are not the same. However, for an ideal gas, where the particles are treated as massless points, they correlate to the same value, which is temperature, because in an ideal gas, the potential energy resultant from interactions with another molecule (e.g. repulsive/attractive forces) is not taken into account when measuring the energy of a particle. Heat (q) put in the system, and not resulting in work (w) acts to change the internal energy ($\Delta U$), which in an ideal gas raises the temperature of a system, and thus increase the average translational kinetic energy of a particle ($KE_{avg}=\frac{3}{2}kT$).