UNIT 4 MEASUREMENT

SECTION 1SPATIAL MEASUREMENTS

( المكاني (المقياس

Shapes ( WARM UP )

Three dimensional & Two dimensional

RevisionWhich parts are Flexible?

Rigid?Round?Non-combustibleConvex?Circular?Cylindrical?Which part leads to the gas

supply?Who is the vertical tube

connected to the rubber tube?What shape is the flame?What are the tubes made of?Where is the air-vent?How is the rubber tube

attached to the horizontal tube?

What properties have the metal and rubber tubes in common?

Vertical tube flame Air-vent horizontal

tube Base rubber

tube A Bunsen burner

RevisionRemember the following expressions

at the top of at the bottom of on the right on the left in the middle of above/over below/under beside Between diagonally above outside inside on either side at the end of far beyond near next to/ adjacent

�قمِة فيأسفل في

�يمين ال على �اليساِر على �منتصِف فيفوقتحت

بجانببين

فوق 7 قطرياخاِرجداخلالجانبين على �نهايِة في

7 بعيدابعد - ما

قDرCببجانب /

مجاوِر

Read this and replace the words in red colour with other expressions

The block of wood has various properties: for example, it is shaped like a cube: its material is wood: the material burns easily: you cannot see through it: the block is difficult to bend, etc.

The block of wood has various properties; for example, it is cubic; it is made of wood; the material is combustible; opaque; the block is rigid, etc.

We can measure the properties of this block.

This block has other properties which are measured. It has height, length and width. Each surface has areas. The area of the cross-section is the cross-sectional area. The area of all the surfaces is the surface area. The volume of the block= length X height X width.

l x h = area (( حِة مسا l x h x w = volume (حجم)

Say which properties of these objects we can measure.

CircumferenceRadiusDiameter

from the to

the

Earth Sun distance

We can measure the radius, the diameter, the circumference and the area of a circle.

We can measure the sides, angles and area of a rectangle, a square and a triangle

We can measure the length of a line.

We can measure the distance from the Sun to the Earth.

Make sentences from the tableExample: The height of large objects is measured in meters.

The

height

volume

area

width

surface area

length

radius

cross-sectional

area

diameter

circumference

distance

of

between

large

small

very

small

objects

places

ismeasured in

m

cm

mm

um

m3

cm3

mm3

m2

cm2

mm2

km

Complete the sentencesThis brick has a

length of 3 cm.It has a height of 1

cm.It has a width of 2

cm.It has a cross-

sectional area of 2 cm2.

It has a surface area of 22 cm2.

It has a volume of 6 cm3.

1cm

3 cm 2 cm

Complete the sentencesThis brick has a length

of 3 cm.It has a height of 1 cm.It has a width of 2 cm.It has a cross-sectional

area of 2 cm2.It has a surface area of

22 cm2.It has a volume of 6 cm3.

1cm

3 cm 2 cm

The measurements of this forest and the trees.

This forest has the length of 10 km.

It has the width of 5 km.It has the area of 50 km2The height of trees is 10mThe measurement of circle.This circle has a radius of

5cmIt has a diameter of 10 cm.It has a circumference of

31.4 cmIt has an area of 78.5 cm2.

Look and read. Exactly (بالضبط) Approximately (7 (تقريبا

The thermometer has a length of exactly 14 cm.The pencil has a length of approximately 14 cm. (exactly

13.9 cm)The knife also has a length of approximately 14cm. (exactly

14.2)This cylinder has a diameter of exactly 20 cm.The tree trunk has a diameter of approximately 20 cm.The rectangular prism has a volume of exactly 6 cm3. The pieces of soap has a volume of exactly 6 cm3.

Section 2 Other measurements Refer to part 2 of the appendix and say whether

the following statements are true or false. Correct the statements.

a) Duration is measured in degrees Centigrade. (F) in seconds, minutes, hours.

b) The second is a unit of time. (T)c) Speed is measured in kilogram per hours. (F) Kmd) The watt is a unit of electrical resistance. (F)

electric power.e) Density is measured in grams per meter cubed.

(F) kilogram per cubic meter. (kg/m3)f) The gram is unit of mass. (T)g) Liquid measurements are made in liters, or cubic

decimeters. (T)

Section 3 Scales an averages Very large and very small quantities (الكميات) are

expressed like this: 106 = ten to the power of six = one million (1,000,000) 10-6= ten to the power of minus six = one millionth. Complete these. 102 = ten the power of two = one hundred (100) 103 = ten the power of three = one thousand (1000) 108 = ten the power of eight = one

billion(100,000,000) 10-2 = ten the power of minus two= one hundredth (

) 10-5 = ten the power of minus five= one hundred

thousandth

1

Ex.9 Make Sentences.The distance to the farthest stars is ten to the power of

twenty six m, ie 100,000,000,000,000,000,000,000 km.The diameter of the Sun is ten to the power of nine meter, i.e. 1,000,000 km ( to convert meter into km delete 3zoro)

The diameter of the Earth is….

The height of Mt Everest is…

A mouse has a length of approx. ten to the power of minus one meter. i.e. ten centimeters.

A cherry has a diameter of… i.e. one centimeter.A blood cell has a diameter of…

The diameter of a sugar molecule is…

Ex.11 Look at the histograms.The histograms in the top row show average range of

temperature (in degrees Centigrade) for each month in three cities. The histograms in the bottom row show their average monthly rainfall (in centimeters).

In Calcutta in January(J) the temperature ranges from 27 0C to 13 0C; that is, the maximum temperature is 27 0C and the minimum temperature is 13 0C. These are the two extremes .of temperature (النهايات)

Complete theses (See part 5 of the appendix for the names of months):

a) Extremes of temperature in Tokyo in January: maximum 10 0C ; minimum -2 0C .

b) In Lima in April the temperature ranges from 15 0C to 28 0C .c) Throughout the year in Calcutta the rainfall ranges from 33

cm to 1 cm.d) In Tokyo the maximum rainfall occurs in the month of

September and minimum rainfall occur in the month of January.

How to calculate the averageThe average rainfall in Calcutta during the first six months of the year.

January 1 cm July 32 cmFebruary 3 cm August 23 cmMarch 4 cm September 24 cmApril 5 cm October 12 cmMay 14 cm November 3 cm June 28 cm December 1 cm Total = 55 cm ÷ 6 = 9.2 cm. Total = 93 cm ÷ 6 =

15.5 Answer these questions:a. Is the figure 9.2 exact or approximate? Exact.b. What is the total rainfall for the second half of the year in

Calcutta? 93 cmc. What is the average monthly rainfall during this period? 15.5 cmd. What is the average rainfall during the last three months of the

year in Tokyo? 11.66 cm

Read this and answer the questions

In Lima the range of rainfall is very narrow (ثابت) Rainfall is fairly constant .(محد)throughout the year. In Calcutta, however, the range of rainfall is very wide. It varies ( Dتفاوتf .a lot ( ي

In which city is there the widest range of temperature? Tokyo.

In which city is the temperature most constant? Lima

Where does the rainfall vary most? Calcutta.

Section 4 ReadingRead the text and find the answers to

these question:

a) Why did early measurements vary? ( ؟ ت�فاوتْت مقاييس مبكرًا� (لماذًا

b) How have measurements become more constant? ( أكثر� ب�حْت ْص

أ� ًالمقاييس كيف(ثباتا�؟

Standards of measurements ( ًالمقاييس) (معاييرIn early times

measurements were made by comparing fِة) ن fاِرfقDبالم )things with parts of the human body. Early units of measurement included the distance from the elbow to the fingers, the width of the hand and the width of the fingers.

Some of these human measurements are still used. For example, the inch is based on the length of half the thumb. A foot was originally the length of a man’s foot. A mile was one thousand walking steps.

Standards of measurements ( ًالمقاييس) (معايير These units were only

approximate, because their standard – the human body- was not constant. Governments tried to standardise( fوحيد للت ب gجرDم )them by using rods of fixed lengths. ( �الثابتِة �األطواِل But these (قضبانrods still varied from country to country.

During the French Revolution, scientists looked for a standard of measurement which (المعياِر)did not change. They chose the distance from the Equator to the North Pole, which is one quarter of the circumference of the Earth. One ten-millionth of this was called one meter and became the basic unit of the metric system.

Other metric units are based on it. For example, the centimeter is one hundredth of a meter. A gram- the unit of weight- is the mass of one cubic centimeter of water.

A standard meter was marked on a platinum bar.( �بالتين The accuracy (حانِة of measuring( الدقِة)instruments was checked by comparing them with this bar. Nowadays the meter is standardized by comparing it with another constant طوِل ) the wavelength –(ثابت) of a certain kind of( الموجِةlight.

Standards of measurements ( ًالمقاييس) (معايير Complete these notes:a) Early units of measurement included the distance from

elbow to fingers, width of hand, width of finger.b) Some human body measurements which are still used,

they include the inch, the foot , the mile.c) These units of measurements were not constant because

their standard was human body. Rods of fixed length were used to standardise them, but these also varied.

d) The distance from the Equator to the North Pole was chosen as the basic unit of metric system .Its length is one millionth of one quarter of the Earth’s circumference. Other metric units are centimeters and millimeters.

e) The standard meter is marked on a platinum bar. Nowadays another constant is used: the wave length of a certain kind of light.