Materials
Material properties
Materials have different properties that make them useful for different jobs. Here are some properties that materials have.
Transparent or opaque
Transparent materials do let light through (you can see through them). Opaque materials do not let any light through (you cannot see through them).
Waterproof
Waterproof materials do not let water through and do not soak up water.
Absorbant
Absorbent materials soak up water and let water pass through them.
Strong or weak
Strong materials are very difficult to break. Weak materials break easily.
Flexible
Flexible materials are easy to bend.
Rigid
Rigid materials are difficult to bend.
Hard
Hard materials are difficult to scratch.
Magnetic
Magnetic materials are attracted to magnets.
Conductors
Some materials are good conductors of heat. This means heat can travel through them easily.
Some materials are good conductors of electricity. This means electricity can travel through them easily.
Some materials are good conductors of electricity. This means electricity can travel through them easily.
Insulators
Some materials are insulators of heat. This means they do not allow heat to travel through them very easily. Some materials are insulators of electricity. This means that electricity cannot travel through them.
Metals
Metals come from rocks called ores.
They are strong, hard and shiny materials that can be hammered into different shapes without breaking.
Many metals are good conductors of heat and electricity.
Some metals are magnetic. Iron is the most magnetic metal. Steel is also magnetic because it is made of mostly iron.
Their properties make them useful for objects such as cutlery, saucepans, cars and coins.
Plastics
Plastics are materials made from chemicals and are not found in nature. They are strong and waterproof, and can be made into any shape by applying heat. Plastics can also be dyed different colours or made to betransparent.
Plastic is not magnetic. It is a good electrical insulator as it does not conduct heat or electricity.
Plastics are used to make all sorts of things, such as bags, bottles and toys.
Glass
Glass is made by melting sand and other minerals together at very high temperatures.
Glass is normally transparent and can be made into many different shapes. Thick glass can be strong, but thin glass will break very easily.
Glass is used for objects that need to be transparent such as windows and spectacles.
Wood
Wood comes from trees.
It is strong, flexible and long lasting.
Wood is used to make things such as furniture that need to be strong and last a long time.
Wood is an insulator of heat and electricity.
Fabrics
Fabrics are made from thin fibres woven together.
- Some fabrics, such as wool, cotton and silk, are natural (the fibres come from living things).
- Some fabrics, such as polyester and nylons are made from synthetic fibres, which are made in factories, from chemicals.
Different fabrics have different properties. Fabrics can be stretchy (a pair of tights),insulating (keep you warm, like a woollen coat) or absorbent (a towel).
Fabrics are used to make clothes as they are flexible and comfortable, can be warm and do not wear out easily.
LINKS--
https://www.youtube.com/watch?v=lK6C-XjD_dQ materials song
https://www.youtube.com/watch?v=TzR9fXL-Obo properties of materials
https://www.youtube.com/watch?v=7IP0Ch1Va44 how paper is made from Wood https://www.youtube.com/watch?v=Gq7L9-0XdVw
https://www.youtube.com/watch?v=svvNNpp4CDs cotton production
https://www.youtube.com/watch?v=CKq42J7SaWw How to make rubber
https://www.youtube.com/watch?v=h-sLHYvqT7I
rubber glove production
https://www.youtube.com/watch?v=9vbTCeYwt_g leather manufacturing process
URL 5.1: Video of paper
making
URL 5.2: Video of making
pencil holder with wooden craft sticks
URL 5.3: Video of
making photo frame with wooden craft sticks
URL 5.4: Video of
cotton production
URL 5.5: Making rubber
(corresponds to Internet Link 5.1 in Textbook)
URL 5.6: Video of
production of rubber gloves
URL 5.7: Video of
leather manufacturing process
URL 5.8: Getting silk
from silkworms (corresponds to Internet Link 5.2 in Textbook)
URL 5.9: Video of
making silk
URL 5.10: Video of wool
production
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