Navy Nuclear Exam 2025 – 400 Free Practice Questions to Pass the Exam

The correct answer describes internal energy as the total of both kinetic and potential energies of a system. Internal energy is a fundamental concept in thermodynamics and reflects the energy contained within a system due to various forms of energy at the microscopic level.

Kinetic energy within a system includes the energies of the particles in motion, such as translational, rotational, and vibrational motions of molecules. Potential energy relates to the interactions between particles, including forces that could do work when particles are rearranged or changed in position.

Understanding that internal energy encompasses both these forms of energy is crucial for analysis in processes such as heat transfer, work done by or on the system, and changes in temperature or phase. This twofold perspective allows for the full characterization of a system's energy state under different thermodynamic conditions.