There are three means of heat transfer: conduction, convection and radiation. This experiment is concerned with conduction and aims at measuring a parameter called thermal conductivity of metals using Searle’s method. The extent to which materials conduct heat can be quantified by a parameter known as the thermal conductivity, symbol k. Conduction is the transfer of heat through a medium, such as solid, where the heat is transferred from molecule to molecule (or electron to electron) but there is no bulk transport of the molecules through the medium. Heat conduction is not only determined by the material, but also by its shape, and by the temperature difference between the two ends. You will probably guess straight away that the higher the temperature difference between the ends, the more heat will flow. The more heat you put to one end of the bar, the more heat will flow to other end. In order to measure the thermal conductivity of a certain material, we need to measure the heat input, its length, its diameter and the temperature difference.