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Thermal conductivity is the ability of a material to conduct heat. In electrical systems, high thermal conductivity is important for dissipating waste heat, particularly at terminations and connections. Copper has a 60% higher thermal conductivity rating than aluminium, [17] so it is better able to reduce thermal hot spots in electrical wiring ...
where is the length of the conductor, measured in metres [m], A is the cross-section area of the conductor measured in square metres [m 2], σ is the electrical conductivity measured in siemens per meter (S·m −1), and ρ is the electrical resistivity (also called specific electrical resistance) of the material, measured in ohm-metres (Ω·m ...
The other isotopes are radioactive, with the most stable being 67 Cu with a half-life of 61.83 hours. [24] Seven metastable isomers have been characterized; 68m Cu is the longest-lived with a half-life of 3.8 minutes. Isotopes with a mass number above 64 decay by β −, whereas those with a mass number below 64 decay by β +. 64 Cu
The resistance of a given element is proportional to the length, but inversely proportional to the cross-sectional area. For example, if A = 1 m 2, = 1 m (forming a cube with perfectly conductive contacts on opposite faces), then the resistance of this element in ohms is numerically equal to the resistivity of the material it is made of in Ω ...
Since most conductive polymers require oxidative doping, the properties of the resulting state are crucial. Such materials are salt-like (polymer salt), which makes them less soluble in organic solvents and water and hence harder to process. Furthermore, the charged organic backbone is often unstable towards atmospheric moisture.
The thermal conductivity of silver is among the highest of all materials, although the thermal conductivity of carbon (in the diamond allotrope) and superfluid helium-4 are higher. [16] The electrical conductivity of silver is the highest of all metals, greater even than copper. Silver also has the lowest contact resistance of any metal. [16]
Conductive textiles known as lamé are made with guipé thread or yarn that is conductive because it is composed of metallic fibers wrapped around a non-metallic core or has a metallic coating. A different way of achieving conductivity is to weave metallic strands into the textile. Some historic fabrics use yarns of solid metals, most commonly ...
In addition, it is known that when single-layer graphene is supported on an amorphous material, the thermal conductivity is reduced to about 500 – 600 W⋅m −1 ⋅K −1 at room temperature as a result of scattering of graphene lattice waves by the substrate, [172] [173] and can be even lower for few-layer graphene encased in amorphous ...