Strength of materials. Elasticity
Before various materials are used in the construction of machinery and buildings, tests are carried out to ensure that they are able safely to stand up to the stresses to which they are likely to be subjected. Industrial laboratories have special apparatus for carrying out these tests. Brittle substances such as masonry and cast iron will support large weights or forces of compression, but will easily break if stretching (tensile) forces are applied. Where tensile forces are involved an elastic material such as steel is used. Elasticity is the ability of a substance to recover its original shape and size after distortion.