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Mott insulators are a class of materials that are expected to conduct electricity according to conventional band theories, but turn out to be insulators (particularly at low temperatures). These insulators fail to be correctly described by band theories of solids due to their strong electron –electron interactions, which are not considered in ...
In solid state physics the electronic specific heat, sometimes called the electron heat capacity, is the specific heat of an electron gas. Heat is transported by phonons and by free electrons in solids. For pure metals, however, the electronic contributions dominate in the thermal conductivity.
Electronic band theory (a branch of physics) explains that electric charge flows when quantum states of matter are available into which electrons can be excited. This allows electrons to gain energy and thereby move through a conductor, such as a metal , if an electric potential difference is applied to the material.
Atmospheric electricity is always present, and during fine weather away from thunderstorms, the air above the surface of Earth is positively charged, while the Earth's surface charge is negative. This can be understood in terms of a difference of potential between a point of the Earth's surface, and a point somewhere in the air above it.
For air at standard conditions for temperature and pressure (STP), the voltage needed to arc a 1-metre gap is about 3.4 MV. [7] The intensity of the electric field for this gap is therefore 3.4 MV/m. The electric field needed to arc across the minimal-voltage gap is much greater than what is necessary to arc a gap of one metre.
Peltier cooling plates / ˈ p ɛ l t i. eɪ / take advantage of the Peltier effect to create a heat flux between the junction of two different conductors of electricity by applying an electric current. [9] This effect is commonly used for cooling electronic components and small instruments.
If a closed circuit consists of conductors of two different metals, and if one junction of the two metals is at a higher temperature than the other, an electromotive force is created in a specific polarity. An example of this is in the case of copper and iron, the electrons first flow along the iron from the hot junction to the cold one.
Thermal conduction property of any gas under standard conditions of pressure and temperature is a fixed quantity. This property of a known reference gas or known reference gas mixtures can, therefore, be used for certain sensory applications, such as the thermal conductivity analyzer.