thermal expansions of materials

Most materials expand when their temperatures increase. The railway tracks, need special joints and supports to allow for expansion. A completely filled and tightly capped bottle of water cracks when it is heated, but you can loosen the lid of a metal jar by running hot water ov..

The constant a , which describes the thermal expansion properties of a particular material, is the coefficient of linear expansion. The units of a are K - 1 or (C O ) - 1 (remember that a temperature interval is same in both the Kelvin and Celsius scales). Fo..

Material α / °C Iron 12x10 -6 Copper 17x10 -6 Steel 11x10 -6 Gold 14x10 -6 Pyrex glass 3x10 -6 soft glass 9x10 -6 ' a ' of iron is 12x10 - 6 / 0 C means, if a rod of length 1m is heated through 1 0 C, then length increases by an amou..

The ability of a material to conduct heat is measured by thermal conductivity (defined below) of the material. Consider a slab of uniform cross-section A and length x. Let one face of the slab be maintained at temperature T 1 and the other at T 2 . Also let..

The coefficient of linear expansion is denoted by the letter ' a ' . Where l = original length The coefficient of linear expansion is a characteristic property of the material of the rod. This means that if rods of same length and at same temperature, but made of diffe..

If we evaluate the increase in volume of the liquid taking into account the expansion of the vessel also, then we say it is absolute expansion of the liquid. We can show that, The coefficient of absolute expansion of a liquid = coefficient of apparent expansion..

An adiabatic process is defined as one with no heat transfer into or out of a system: dQ=0. We can prevent heat flow either by surrounding the system with thermally insulating material or by carrying out the process so quickly that there is not enough time for appreciable heat f..

Glass - Ordinary glass is a mixture of sodium and calcium silicates and is made by heating a mixture of sand (essentially SiO 2 ) with sodium carbonate and calcium oxide in a furnace at around 1700K and cooling rapidl..

Introduction - A dynamic environment of matter and material surrounds man. Since his birth he has been exposed to these changing surroundings. His curiosity to understand his surroundings and the events occurring around him, has led him to systematically enquire and collect information th..