Unit 7 Technology Around Us - Note

• There are limitations to human abilities.
• We cannot memorise too many numbers, jump too high or read from a long distance.
• Devices are used to overcome human limitations.
• Microscopes and magnifying glasses are devices used to see fine objects.
• Microphones and telephones enable someone far away to hear us.
• Cars and aeroplanes allow us to travel far.
• The development of technology is for the betterment of mankind.
• Technology is invented to solve problems in our daily lives.
• Technology has its advantages and disadvantages.
• Technology can benefit mankind if used wisely. 

Unit 7 Technology Around Us - Lesson 4

Lesson 4 Advantages And Disadvantages

Technology can benefit us if used wisely. 


What are the advantages and disadvantages of polystrene containers?


To keep food and drink cold or hot. 
It is not good and safe for nature.
It is cheap.


Can you name other benefits of polystrene to mankind in our daily life?

Unit 7 Technology Around Us - Lesson 3

Lesson 3 Solving Problems


Here are some examples of problems that you may encounter in your classroom. 

Problems faced in classroom

Solutions 

Unit 7 Technology Around Us - Lesson 2

Lesson 2 Development Of Technology

Humans develop technology for the betterment of mankind. This development has made the world a better and more comfortable place to live in.

Technology In Agriculture

A long time ago, simple devices were used to dig holes, and loosen the soil. When humans discovered metal, they invented devices to plant crops. Later, animals were used to plough the land.

Unit 7 Technology Around Us - Lesson 1

Lesson 1 Human Limitations

Technology is important in everyday life. Imagine life without technology.

What else can our senses and body allow us to do?

However, there are limitations to what humans can do.

Soalan Unit 6

1.  The biggest planet in the Solar System is

            A         Mars

            B         Earth

            C         Jupiter

D         Mercury

   2.  In our Solar System, Earth’s nearest neighbour is the

A         Sun

B         Moon

C         planet Mars

D         planet Venus

Unit 6 The Earth And The Universe - Note

• The main constituents of the Solar System are the Sun and the planets.
• The sequence of planets starting from the Sun are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto.
• The planets differ in size and distance from the Sun.
• The planets have very different conditions on their surfaces.
• The Sun is in the centre of the Solar System.
• The Sun is very big compared to the planets.
• All planets move round the Sun.
• The ratio of the size of the Moon to Earth and to the Sun is 1:4:400.
• The distance from Earth to the Sun is 400 times the distance from the Moon to Earth.
• Earth has water, air and a suitable temperature to support life.
• If Earth is too near to the Sun, it will be too hot to support life.
• If Earth is too far to the Sun, it will be too cold to support life.
• Earth is the only planet in the Solar System that has life on it.  

Unit 6 The Earth And The Universe - Lesson 3

Lesson 3 Planets, Planets How Are You?

• Mercury 
•  It is too close to the Sun. The temperature is too hot to support life. 

• Venus 
• A great amount of the heat from the Sun is trapped in its atmosphere. This makes it hotter than Mercury. 

• Earth
• It has water, air and a suitable temperature to support life. 

Unit 6 The Earth And The Universe - Lesson 2

Lesson 2 How Far And How Big


How big is the Sun, the Moon and Earth?
How far is the Sun and the Moon from Earth?

Scientists have calculated that the Sun is one hundred times the size of Earth. Earth is four times the size of the Moon. 

Size	Ratio
Moon	1
Earth	4
Sun	400

The distance from Earth to the Sun is 400 times the distance from Earth to the Moon. 

Distance from	Ratio
Earth to Moon	1
Earth to Sun	400

Unit 6 The Earth And The Universe - Lesson 1

Lesson 1 Our Solar System

The sun and the nine planets are part of the Solar System. The nine planets are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto. The Sun is in the centre of the Solar System. All the nine planets move around the Sun in a large oval path. The planets also spin by itself. 

Our Solar System - Size Of Planets and Stars to Scale

Scale of Earth, Sun, Rigel, and VY Canis Majoris.

Soalan Unit 5

1.  Object M can float in water but object N cannot. M and N are respectively

	M	N
A	plastic ruler	metal fork
B	rubber slipper	plastic cup
C	paper	ice-cream stick
D	coin	wooden ruler

2.  Which of the following is not true ?

	Object	Resource
A	Flower pot	Soil
B	Leather shoe	Animal
C	Wooden chair	Plant
D	Wooden table	Petroleum

Unit 5 Materials - Note

• Objects can be classified according to the materials they are made of.
• Different materials have different properties.
• Non-metals are generally good insulators of heat and electricity.
• A good conductor of heat is also a good conductor of electricity.
• Materials can be classified based on their abilities to allow light to pass through.
• Materials can be transparent, translucent and opaque.
• Suitable materials can be used to keep hot things warm and cold things cool and chill.
• Materials chosen to make objects are based on their properties.
• Some materials can float and absorb water. Some can be stretched.
• Man-made materials come from natural materials.
• Natural materials are limited in supply. 

Unit 5 Materials - Lesson 9

Lesson 9 Rusting

• This car is made of iron. This part of the car has rusted. 

• The nail with a rusted surface is dull and rough. When you scrap it off, the rusted surface will blister off. The clean non-rusted surface stays shiny. Rusted surfaces are ugly. 

Unit 5 Materials - Lesson 8

Lesson 8 Reuse, Reduce And Recycle


Natural and man-made materials are very limited. What should we do with them?

Unit 5 Materials - Lesson 7

Lesson 7 Natural And Man-Made Materials


Observe the materials around you. These materials are either natural materials or man-made materials. Natural materials are found in nature. Man-made materials are made by man.

•  An eraser is made of rubber. Rubber and silk are natural materials. Do you know why?

Unit 5 Materials - Lesson 6

Lesson 6 Combined Uses Of Materials


Different materials can be used to make an object. 

•  The casing of an electric plug is made of plastic or porcelain because these materials are insulators of electricity. The pins are made of metal because it is a conductor of electricity. 

Unit 5 Materials - Lesson 5

Lesson 5 Choosing Suitable Materials

We use heat insulators to keep things hot or cold. These heat insulators trap air. The trapped air cuts down heat from going through the material.

Polystyrene materials contain trapped air. They are good insulators of heat. They are used to make food containers.