Physical Science deals with non-living systems and explains how matter behaves, how energy is produced and transformed, how forces cause motion, how measurements are made, and how simple electronic devices work. This unit equips teachers with the scientific knowledge needed to explain everyday physical phenomena in a simple and logical way.

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MODULE 3.1: MATTER AND ITS PROPERTIES

Meaning of Matter

Matter is anything that has mass and occupies space. This means that anything we can see, touch, or feel—such as air, water, stones, books, and our bodies—is matter.

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States of Matter

Matter exists mainly in three states:

1. Solid

• Solids have a definite shape and definite volume.

• The particles in solids are closely packed and vibrate in fixed positions.

• Solids are not easily compressed.

Examples: stones, wood, chalk, ice

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2. Liquid

• Liquids have a definite volume but no definite shape.

• They take the shape of their container.

• Particles are loosely packed and can slide past one another.

Examples: water, kerosene, palm oil

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3. Gas

• Gases have no definite shape and no definite volume.

• They spread to fill the entire container.

• Gas particles are far apart and move freely.

• Gases are easily compressed.

Examples: air, oxygen, carbon dioxide

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Properties of Matter

Properties are characteristics that help us identify and describe matter. They are grouped into physical properties and chemical properties.

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Physical Properties

Physical properties are characteristics that can be observed without changing the substance.

Examples include:

• Colour

• Shape

• Size

• Density

• Solubility

• Melting point

• Boiling point

Example: Ice melting into water is a physical change because the substance remains water.

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Chemical Properties

Chemical properties describe how a substance reacts to form a new substance.

Examples include:

• Flammability (ability to burn)

• Rusting

• Reactivity with acids

• Corrosion

Example: When iron rusts, it changes into iron oxide. This is a chemical change.

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Changes in Matter

Physical Changes

• No new substance is formed.

• The change is usually reversible.

Examples: melting, freezing, evaporation, dissolving salt in water

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Chemical Changes

• A new substance is formed.

• The change is usually irreversible.

Examples: burning wood, rusting iron, cooking food

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Interaction of Matter

Matter can interact through:

• Mixing

• Heating

• Cooling

• Chemical reactions

These interactions explain many daily activities such as cooking, washing, and fuel burning.

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MODULE 3.2: ACIDS, BASES, AND SALTS

Acids

An acid is a substance that:

• Produces hydrogen ions (H⁺) in water

• Has a sour taste

• Turns blue litmus paper red

Examples:

• Hydrochloric acid

• Sulphuric acid

• Citric acid (in oranges and lemons)

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Bases

A base is a substance that:

• Produces hydroxide ions (OH⁻) in water

• Feels slippery

• Turns red litmus paper blue

Examples:

• Sodium hydroxide

• Calcium hydroxide

• Soap

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Salts

A salt is formed when an acid reacts with a base in a process called neutralisation.

Example:
Hydrochloric acid + Sodium hydroxide → Sodium chloride + Water

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Properties of Acids and Bases

Property	Acids	Bases
Taste	Sour	Bitter
Litmus	Blue → Red	Red → Blue
Reaction	React with metals	Neutralise acids

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Everyday Examples

• Vinegar → Acid

• Lime water → Base

• Common salt → Salt

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Importance in Daily Life

• Acids are used in batteries and cleaning agents.

• Bases are used in soap making.

• Salts are used for cooking and food preservation.

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MODULE 3.3: MEASUREMENT OF PHYSICAL QUANTITIES

Meaning of Measurement

Measurement is the process of comparing an unknown quantity with a known standard unit.

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Physical Quantities and Their Units

Quantity	SI Unit	Instrument
Length	metre (m)	ruler, tape
Mass	kilogram (kg)	balance
Time	second (s)	clock
Temperature	kelvin (K)	thermometer

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SI Units

The International System of Units (SI) is used worldwide to ensure uniformity in measurement.

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Unit Conversion

Sometimes measurements must be converted from one unit to another.

Examples:

• 1 m = 100 cm

• 1 kg = 1000 g

• 1 hour = 3600 seconds

GTLE Focus: Candidates are often tested on simple conversions and calculations.

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MODULE 3.4: ENERGY AND ITS TRANSFORMATION

Meaning of Energy

Energy is the ability to do work or cause change.

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Forms of Energy

1. Heat Energy – causes objects to become warm

2. Light Energy – enables us to see

3. Electrical Energy – powers appliances

4. Chemical Energy – stored in food and fuels

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Sources of Energy

• Sun (solar energy)

• Water (hydroelectric power)

• Fossil fuels

• Wind

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Energy Transformation

Energy can change from one form to another.

Examples:

• Electric iron: electrical → heat

• Torchlight: chemical → electrical → light

• Human body: chemical → mechanical

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Importance

Energy transformation explains:

• Electricity generation

• Transportation

• Cooking

• Industrial processes

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MODULE 3.5: FORCE, MOTION, AND PRESSURE

Force

A force is a push or pull that can:

• Change the shape of an object

• Change its speed

• Change its direction

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Newton’s Laws of Motion

First Law

An object remains at rest or in motion unless acted upon by a force.

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Second Law

Force = mass × acceleration
This means heavier objects require more force to move.

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Third Law

For every action, there is an equal and opposite reaction.

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Motion Concepts

• Displacement: distance in a given direction

• Velocity: speed in a given direction

• Acceleration: rate of change of velocity

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Pressure

Pressure is force per unit area.

Applications:

• Sharp knives cut easily

• Wide tyres reduce pressure on soft ground

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MODULE 3.6: BASIC ELECTRONICS

Meaning of Electronics

Electronics deals with the flow of electric current through circuits.

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Simple Electric Circuit

A simple circuit consists of:

• Power source (battery)

• Connecting wires

• Load (bulb)

• Switch

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Circuit Components

Component	Function
Battery	Supplies energy
Switch	Controls current
Bulb	Produces light
Resistor	Limits current

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Uses of Electronics in Daily Life

• Mobile phones

• Radios

• Televisions

• Computers

• Traffic lights

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SUMMARY FOR GTLE

This unit tests:

• Conceptual understanding

• Calculations

• Practical applications

• Everyday examples

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