Question

Joining a metal wire to both ends of a bettery causes current to flow through it.

Also, the flowing current in turn produces magnetic field that kind of rotates around that wire.

Can we call this current, and the subsequent magnetic field, thermodynamic quantities?

Thermodynamic quantities-–––––––––––––––––––––––––––
are those quantities that characterises the state of a system. For example, temperature, pressure, number of particles, volume, magnetisation etc.
What I think is - when current is passing through the wire, it causes Joule heating. Resulting in a temperature T=i²Rt
. And since temperate is a thermodynamic quantity, its defining quantity current should be a thermodynamic quantity also.
But produced magnetic field has no such function. So it is not a thermodynamic quantity.

What should be the correct answer?

Edit: After hyportnex's comment, I realized I have mistakenly written T
as temperature, whereas the correct word is heat generated.

Answer 1

Electrical current is not a thermodynamic quantity, but the heat generated from resistance (Joule heating) in a conductor is. Magnetic fields are electromagnetic phenomena and do not fall under thermodynamic quantities. Superconductors allow current without heat, an exception in electrical conduction.

Step-by-step explanation:

The concept of current producing a magnetic field and the resulting heat from a conductor due to resistance can be misleading when classifying them under thermodynamic quantities. Electrical current itself is not directly considered a thermodynamic quantity. However, when current passes through a material with electrical resistance, such as a metal wire, it results in Joule heating, where electrical energy is converted into heat energy. This heat energy can certainly be classified as a thermodynamic quantity because it describes the transfer of energy as heat within the system, affecting temperature, which is a fundamental component of thermodynamics. On the other hand, the magnetic field generated by the passing current is more appropriately categorized under electromagnetic phenomena, rather than thermodynamic quantities, as it does not characterized the energetic state of a system in the way that temperature or pressure does.

Materials such as metals, in general, are both good electrical and thermal conductors. When electrons collide with the atoms in the conductor during current flow, the kinetic energy of the electrons is not increased, instead, it's transferred to the atomic lattice of the conductor, leading to an increase in temperature which is evident in devices like incandescent light bulbs, where the tungsten filament glows due to heat generated from current.

In contrast, superconductors provide an interesting exception to the above case. They can maintain a steady current without the need for continuous power input, exhibiting zero resistance and, as a result, no Joule heating. This unique property of superconductors allows for the flow of current without the accompanying thermal effects typically associated with current flow in conventional conductors.