materials (part ii)
TRANSCRIPT
Materials. (part II)
INDEX: • Natural materials and manufactued materials. pg 3• Properties of materials pg 12
- transparent/opaque- rough/smooth- hard/soft- flexible/rigid- absorbent/waterproof
In this lesson we will learn the difference between:
natural materials and manufactured materials.
Natural materials are found in nature.
They come from plants…Cotton Wood Cocoa
animals, ...Sheep
Silkworms
Horse
Alpaca
and rocks.Diamond
Iron
Copper
Gold
Silver
Sand
Humans use natural materials to make new materials. These new materials are called: manufactured materials.
Petroleum is a natural material A plastic ruler is a manufactured material
NATURAL MATERIALS MANUFACTURED MATERIALS
horsehair
violin bow
NATURAL MATERIALS MANUFACTURED MATERIALS
iron
cocoa
NATURAL MATERIALS MANUFACTURED MATERIALS
gold
Now, enjoy the next videos.
From mud to a clay pot.
From natural rubber...
… to boots
… to rubberbands
Properties of materials.
Part one.
Look through different materials. What do you see?
Some materials are transparent. You can see clearly through them.
Can you name any transparent materials?
Glass is transparent.
Why is it important for these objects to be transparent?
Other materials are opaque. You cannot see through them.
Can you name some opaque materials?
Wood and metal are examples of opaque materials.
Think of the walls of your house/flat. Are they transparent or opaque? Why?
Part 2.
What do you feel?
Materials can be rough or smooth.
Ro
ugh
Smooth
Is your skin rough or smooth?My skin is…
Put a piece of paper on three different surfaces. Rub your cryon and observe the result.
Materials can be hard or soft.
hard soft.
Find three hard objects and three soft objects.
Materials can be flexible or rigid.
Are rulers flexible or rigid? Rulers can be…
Are trees flexible or rigid?
Is your body flexible or rigid?
Find three flexible things. and three rigid things.
Remember…
Part three.Get wet!
How does water affect different materials?
Some materials are absorbent.
mop
spongecotton
towels
Cleaning cloth
Towel paper
Absorbent materials can take in water
or another liquid.
Other materials are waterproof.
Waterproof materials do not let water
go through.
Is your coat absorbent or waterproof?
How about your shoes/boots?
Is paper absorbent or waterproof?
Is your folder waterproof?
Is your skin absorbent or waterproof?