Internal Energy

Show/Hide Sub-topics (Thermal Physics | A Level)

The internal energy is the total microscopic kinetic and potential energies of the particles (atoms and/or molecules) composing the system.

$U = \sum E_{P} + \sum E_{K}$

U is a function of state(depends on state of system).

T increase­ $\rightarrow$ Speed increases $\rightarrow$ microscopic KE ­increase $\rightarrow$ U ­increase

To measure temperature quantitatively and objectively, a device is required.