Notes

TOPIC 1: HARDWOOD AND SOFTWOOD

Hardwood is wood from deciduous trees. they are usually found in brood-leaved temperate and tropical forest. mostly deciduous but in tropics and subtropics evergreen
Softwoods are from gymnosperm trees such as conifers. these are grown cold climate which is the wood from angiosperm trees.
CHARACTERISTICS OF HARD AND SOFTWOOD
GRAIN: softwood do not have Ressel and therefore have a softer, less pronounced grain than hardwoods, which are characterized by heavy, distinctive grain
colour: Hardwoods tend to be darker than softwoods, which are often lighter.
Hardness: hardwoods are usually stronger, more scratch resistant.

TOPIC 2: INTRODUCTION TO WOOD
Wood is a natural, organic material that is derived from the stem, branches, roots and woody plants.
Properties
Density: wood is less dense than many other materials, making it right weight and easy to handle.
Strength: woods natural fibers provide both tensile (stretching) and compressive (squeezing) making it strong and capable of supporting, heavy tools.
Durability: properly treated and maintain wood is resistant to decay, fungi and pest.
air is natural while kiln is artificial.

TOPIC 3: METAL
Metals are class of chemical elements characterize by their specific physical and chemical properties. They are typically solid at room temperature having a shinning metal luster and are good conductors of heat and electricity.
PROPETRIES OF METAL
1. MALLEABILITY: Metals can be easily hammered, rolled or pressed into different shapes and without breaking. this allows for the production of thin sheets, wires and various forms of metal production.

2. CONDUCTIVITY: metals are of heat and electricity. This makes them essential or electrical wiring heating system and electronic devices.

3. DENSITY: Metals tend to be dense materials which means they have a high mass in a given volume. high density is advantages for many applications such as coin making.

4. STRENGTH: Metal is known for strength and durability, and they are used in construction, Machinery and Transporation. because of their ability to withstand pressure and stress.

5. LUSTER: Most metals have shinny and reflective metal and it aids to the aesthetic appeal and decorate items and jewelry
6. Ductility: Metal can be stretch into thin wires without braking
TYPES OF METAL
1. Aluminum
2. Copper
3. Gold
4. Iron
5. Silver
DIFFERENCES BETWEEN METAL AND WOOD
1. Wood is a natural material that comes from trees, while metal is a synthetic material that is made from ores
2. Wood is a poor conductor of heat and electricity while metal is not
3. Wood is less dense than metal.
4. Wood also has a lower melting point than metal.
5. Some types of wood can be quite flexible, while metals tend to be more rigid.
6. Sound Absorption: Wood absorbs sound, rather than reflecting or amplifying.