5. The total potential and kinetic energy of the particles in an object is called?

The total kinetic energy of all the particles is called the thermal energy or thermal kinetic energy of the object. This is opposed to the kinetic energy of the whole object (like a moving object) and the kinetic energy of a single particle. However, the particles also have their own potential energy.

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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