Science form 1 chapter 1

Science

Chapter 1 Introduction To Science

1.1 Science is Part of Everyday Life1.2 Steps in a Scientific investigation1.3 Physical Quantities and Their Units1.4 The Use of Measuring Tools1.5 The Concept of Mass and Weight

What is science?

Science is a study of the natural environment and natural phenomena.

Science enables us to understand events which take place in our everyday life.

Understanding natural events helps us to avoid disasters, overcome problems and lives a more comfortable life.

Science is always expanding because scientists are always trying to find answer to their many questions about the environment.

Examples of natural phenomena

Formation of ice Eruption of a volcano Germination of seed Growth of living things

Uses and benefits of science

Our knowledge of science has given us many benefits. Technology is the application of our scientific knowledge to help

us in our daily work. Science and technology have greatly helped to make life easier

for us and to make us live longer.


Leisure : Science enables us to enjoy our leisure by having inventions such as the radio, television, motor vehicles and computers.

Easier work : Science makes our work easier. Machines such as washing machines, and microwave ovens help us to do our work faster and use less energy.

Construction : Buildings, condominiums, supermarkets, bridges, dams and roads are being built very fast due to the use of science and modern technology.

Agriculture : Science has provided farmers with machines such as tractors which can plough their land quickly and effectively. Chemical fertilizers and pesticides formulated by scientists have increased the yields from crops.

Transport : Science has invented machines which enable us to move over land (motor vehicles), on water (ships), under the sea (submarines) and in the air (aeroplane) very quickly and safely.

Medicine : Science has discovered new drugs to fight diseases effectively. Science has enabled surgeons to perform open heart surgery and to transplant organs from one person to another. All this has increased our life expectancy.

Communication : Science has made it possible for us to communicate with people in far away countries due to inventions such as the mobile phone, television, Internet and Information Communication Technology (ICT).

Space Exploration : Modern science and technology have enabled astronauts to travel into outer space and study the planets and the Universe.

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Careers in science

Science has many branches. Each branch deals with one particular aspect of our natural environment.

Each branch of science offers many careers in specialized jobs. Some branches of science are given below.


Some careers in Science

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Science careers

Biology

Botany

Zoology

Physics

Electronics

Chemistry

Pharmacy

Medicine

Geology

Meteorology

Astronomy

A Science Laboratory

Scientists can work anywhere. A scientists studying tropical plants and animal for example, could make the Malaysian jungle his laboratory. However, most scientist do their experiment in laboratory.

However, some chemical are dangerous. We need to handle these chemical carefully. We need to know about safety in laboratory.

Hazardous symbols

Chapter 1 Introduction To Science Science

Common laboratory apparatus

Chapter 1 Introduction To Science Science


Way to use Bunsen burner

Close the air hole completely by turning the collar. Hold a lighted match or wooden splinter near the mouth of barrel. Turn on the gas slowly. When the flame is seen, slowly open the air hole by turning the collar.

Bunsen burner

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Luminous flame versus non-luminous flame

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Steps In A Scientific Investigation Chapter 1 Introduction To Science

Experiment : (title)

•Problem :•Hypothesis :•Variables :

–Constant variable :–Manipulated variable :–Responding variable :

•Materials/ apparatus :•Procedure :•Result :•Discussion :•Conclusion :

The Scientific Method

Identifying the problem

Making a hypothesis

Planning an experiment

Controlling the variables

Collecting data from the experiment

Analysing and interpreting the data

Forming a Conclusion

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Physical Quantities and their Units

A physical quantity is a quantity that can be measured. Examples of physical quantities are length, time, mass, temperature and electric current.

Physical quantities are measured in S.I. units. The S.I. symbol is an abbreviation for the French term Systeme International d’Unites. It means International system of units.

Basic quantities


Prefixes used in measurement

Prefixes are useful in expressing physical quantities that are very big or very small.

The value of physical quantity can be changed to prefix form. See the examples below.

1. Write 840 000g with the kilo prefix.2. 840 000/1000 = 840kg

Physical Quantities

S.I. unit Symbol Instrument

Length

Mass

Time

Temperature

Electric current

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Value of physical quantity Prefix form

0.005m

250g

4 000 000K

0.000 003A

0.5cm

9000kg

3MK

0.006m mm


Measuring Tools

Measuring length

The S.I. unit of length is in metre (m). Millimetre and Centimetre are also used to measure length. The

unit kilometre (km) is usually used for longer distances.

Measuring a straight line

When you are reading the scale on a ruler, place your eyes in the correct position.

Otherwise, there will be a parallax error in your reading. This error occurs as a result of a change in the observer’s position.

Make sure your eye is straight above the end of the object to avoid parallax error.

When using a thick ruler, stand the ruler on its edge during measurement.

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Measuring a curve

The length of a curve can be measured using thread and a ruler. Align the thread on the curve. Mark the thread at the beginning and at the end of the curve. Pull the thread straight along a ruler and measure the length

between the two marks on the thread.

Measuring diameter using callipers

There are two types of callipers, internal callipers and external callipers.

External callipers are The external callipers are placed on the outside surface of the

object. The callipers are then carefully transferred to a ruler to get a

reading and must be transferred without changing the width.


Internal callipers are The internal callipers are placed on the inside surface of an

object. Again, the callipers must be transferred carefully to the ruler to

get a reading.

Measuring area

The S.I. unit for area is square metre (m2). Other units that can be used are square centimetres (cm2) and

square millimetres (mm2). The area of a regular shape can be easily determined through

simple measurements and calculations. However, some objects have irregular shaped. The area of a

irregular shape can be determined by using graph paper.

A square that is half-covered or more than half-covered by the irregular shape is counted as full square.

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Measuring volume

The volume of an object is the amount of space filled by the object.

Volume can be measured by using a measuring cylinder, burette, pipette, or volumetric flask.

Volume of a liquid

The unit commonly used for measuring the volume of liquid is millilitre (ml) and litre (l).

When taking reading, make sure your eyes is level with the meniscus. For most liquids, the meniscus is the lower level of the liquid surface.

However, the meniscus of mercury is the higher level of the liquid surface.

To make it easier to read the scale, place a piece of coloured paper behind the measuring cylinder.

Volume of a solid

The units normally used for the volume of a solid are cubic metre (m3), cubic centimetre (cm3), and cubic millimetre (mm3).

The water displacement method is used to measure the volume of a solid.

The volume of a solid can be measured directly using a measuring cylinder or indirectly with an eureka can (see diagram above).

The volume of a solid is equals to the volume of water displaced.

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The concept of mass and weight

Weight

Weight can be scientifically defined as the force acting on an object due to gravity.

An object’s weight is actually the mass multiplied by the force gravity. Thus, weight depends on gravity.

Weight = Mass x gravity

Weight may change at different locations. If the gravitational force applied is different, then the weight measured will be different.

The S.I. unit of weight is newton (N).

Mass

Mass is the amount of matter an object contains. Unlike weight, the mass of an object does not change at any

locations. External force has no effect on mass.

The S.I. unit of mass is kilogram (kg). Smaller unit for mass are the gram (g) and milligram (mg).

1 kg = 1000g1g = 1000mg


Difference between mass and weight

Weight Mass

Value

Measuring unit

Measuring equipment

Characteristic

Science form 1 chapter 1

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