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History of wood. Wood is probably one of Man’s oldest natural resources as a household article is as old as time itself.
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History of wood • Wood is probably one of Man’s oldest natural resources as a household article is as old as time itself. • Archaeologist exvacations have uncovered wooden utensils and dating back thousands of years which, if examined closely, resemble many of the basic spoons and tools we use today. • Because wood it is a relatively cheap natural material which is easily worked, wood is widely used to make quality products used in the preparation of food.
Properties and uses of wood • It is anisotropic ( structures and properties vary in different directions). • It is hygroscopic ( ability to attract moisture from the air) . • It can shrink and swell. • It is compressible. • It can be bent. • It has tension. • It is a source of fuel. • Serves as a great insulator. • Has interesting implications in the construction of violins, other stringefd musical instruments and sound boards in pianos.
History of wood • Wood is probably man’s oldest natural resource and its history dates back to about a thousand years. • Archaeological excavations have uncovered wooden utensils and bowls dating back thousands of years which, when examined closely, resemble many of the basic spoons and tools that we use today.
Properties Hard Strong Durable Floats on water. Uses Burned in most rural areas for fuel. Wood is used for cutlery, such as chopsticks, toothpicks, and other utensils, like the wooden spoon. Used for building houses and boats. Propertiesand uses
Brief history of glass Glass was first made in coastal north Syria, Egypt, around 1500BC. It was used as a glaze for pottery and other items. Glass is made from silica, a hard substance found in sand. It can stand up to effects of wind, rain or sun. Uses of glass Common daily things such as : Utensils, window panes, mirrors, spectacles, telescopes. It also plays an essential role in science and industry. It can be used for laboratory equipment, container glass etc.
Properties of glass • Brittle • Transparent • Waterproof • Hard • Heavy • Sinks in water • Non-magnetic • Non-conductor of heat • Non-conductor of electricity
Properties of Glass • Glass refers to a hard, brittle, transparent amorphous solid. • Glass is an inorganic product of fusion which has been cooled to a rigid condition without crystallizing. • In the scientific sense the term glass is often extended to all amorphous solids.
What glass is made from:Uses of glass: Ingredients for making glass • Pure Silica • Sodium Carbonate • Lime • Magnesium Oxide • Aluminium Oxide Uses of glass • Windows • Bottles • Eyewear • Mirrors