Silver metal. Protected silver has greater optical reflectivity than aluminium at all wavelengths longer than ~450 nm. At wavelengths shorter than 450 nm, silver's reflectivity is inferior to that of aluminium and drops to zero near 310 nm. Very high electrical and thermal conductivity is common to the elements in group 11, because their single s electron is free and does not interact with the filled d subshell, as such interactions (which occur in the preceding transition metals) lower electron mobility. The electrical conductivity of silver is the greatest of all metals, greater even than copper, but it is not widely
Thermal conductivity are "additive". Thus, when heat flows consecutively through two components each with a resistance of 3 °C/W, the total resistance is 3 °C/W + 3 °C/W = 6 °C/W. A common engineering design problem involves the selection of an appropriate sized heat sink for a given heat source. Working in units of thermal resistance greatly simplifies the design calculation. The following formula can be used to estimate the performance: where: For example, if a component produces 100 W of heat, and has a thermal resistance of 0.5 °C/W, what is the maximum thermal resistance of the heat sink? Suppose the