Final answer:
Internal energy is the total measure of all forms of energy in a thermodynamic system, crucial in understanding energy transfer in physics.
Step-by-step explanation:
The measure you're referring to is known as internal energy, which is a key concept in thermodynamics. Internal energy is the measure of the total energy of a thermodynamic system, encompassing all forms of energy present within, including kinetic and potential energies of the particles.
This internal energy is what is transferred between the system and its surroundings either as heat or work, defining how energy is conserved and transformed in physical processes.
Systems can be either open, closed, or isolated based on their ability to exchange energy and matter with their surroundings. An open system like a stovetop allows for the transfer of energy to its surroundings, whereas a closed system does not.