/ For :

Fron :

'c403020100

-10

L esson

q *r;sh

403020100

-10

Crn

n Kead;ng Ts ttes Grup hs r t) idg Glrrs

For Sc;ence €nd TLchnologyC Ger.eral Sc.gsa.e, )

bJ w'tortin Bales et.ol ., lgfa

'C Tokyo 'C Lima

11. Look at these histograms:

JFMAMJJASONDtomperatura

JFMAMJJASONDtemparature

JFMAMJJASONDtemp6rSture

Now read this:

Total

Ans*'er these questions :

-10The average monthly rainlall in Calcutta during the first si_r monthsof the year is:

January I cmFebruary 3 cmMarch 4 cmApril 5 cmMay 14 cmJune 28 cm

Cm30)tr,

20t510

50

Cm302520l5.lo

55cm=6:9-2cm

Now read this:

The hisrograms in the top row show the ave rage rangt, of terrpcrature(in degrees centigrade ) for each nronth in three cities. The hisi'gramsin the bottom row show their average monthly rainlall (in centinretres).

In Calcutta in January the temperature ranges from 27.C to ll',C:that is, the ma-vimum tempcrature is 27''C and the minintunt tcmpera-ture is l3'C. These are the two extremcs of tcmperature .

Complete these (see part 5 ol the appendix for the narnes of months):

a) Extremes of temperature in Tokyo in January: maximunr ___,mlnlmum

b) In Lima in April thec) Throughout the yeu

to i cm.

temperature ranges from _ toin

-

the rainlali rangis l-r.rrn .lj cm

d) In Tokyo the maximum rainfall occurs in the month ofand the minimum rainfall . . .

e) Is the figure 9.2 exact or approximate?f) What is the total rainfall for the second half of the vear in

Calcutta?g) What is the average monthly rainfall during this period?h) What is the average rnonthly rainfall during the last three

months of the year in Tokyo?

Now read this and answer the questions:

In Lima the range of rainfall isvery narrow. Rainfall is fairly constantthroughout the year. In Calcutta, however, the range of rainfall isvery wide.It varies alol.

i) In which city is there the widest range of temperature?j) In which city is the temperature most constant?k) Where does the rainfall vary most?

Calcutta

n-" JFMAMJJASONDrainfall

o:?mmi:m6ra inf all

JFMAMJJASONDrainfall

33

i.{ow iook at this bar-graph:

*LTilt;re the heights of rhe mounrains, makin-s sentences from rhe rwo

Example: Everest is nearly nine tirnes as high as Ben Nevis.Aconcagua is considerabiy highei than Mont Blanc.

the same height astwice as high as . . .

x times as high as .

higherlower

I

I

than

5' Now read these staternents and then complete the bar-graph, which showsthe lengths of rivers.

nearlyapproximately

muchcorfsiderablyslightly . .

'iG

E.otEo

ocooE5o

!C1a

oca

.s!al'6c

The Nile is approximately l6 times as long as the Thames.The Amazon is slightly ,ho.te, than the Nlle.J.he _{ya.zon is approiimately I,000 t- long". than the yangtse.The Nile is approximately twice u, fonlur-tt. Volga and the paranaIlr. Lulunq is slightly tonger tf,an tfreTof sa.I ne Volga ls considerably longer than rhetuphrates.The Euphrates is much longerit an th"-ii;.r.

The reiative heiglhts of Mountains

Read and complete rhis:

_=-=-to

The rectangles show the heights of differentThe heights are marked on"the

--.-'-;;jr.thousands of ._.-_-- fne leights of tirlse'

(horizontal axis)

Argentina Tanzania

mountains.The scale is shown in

mountains range from

234length in thousands o{

56kilometres

o3oocoo

oqC

s\2

oco

co

co

80

- Section 2 Fercentages anrl ratios5. Look and read:

This chart shows the relati'e numbers ol stucients in differentfaculties of a university. you can see that tlrc nta joritl,(the ureaterpart) ol students study scientific or technical subjects. whereasstudents of letters are in tlrc ntirtoritt,.

The proportions are approximate. They can be expressed as pcr-ce,tugc:t. J'hus, science students t.ortt.tiruit appr.oximateil 30 ?"(thirty per cent) of all students.(Note: A consists of B : B cons{itutes A.)

Now complete these statements:

Engineering studcnts . . . cf a,ll students.50:,; oi ail studenis studl'

-

orThe

-

of studerrts in thc faculties of engineering and lettersare approximately the same.

d) There are _ lew students of education.e) _ the percentage of science students, the percentage oi

agricuiture students is relatir,,eiy small.Q In the faculty of science, 70lof the students are men and 30,)(

are women; that is, the ..- are men and women are inthe

g) Approximately 15 \ of ali sruCents stud_v _.

7. Make questions and answers like the example.The proportions can also be expressed as ratio.s.

or: The ratio ol students ofscience to students ofengineeringis 3 :2.

Now write some similar statements about students in your college oruniversity.

8. Look and read:

Alloys are mixtures of metals indifferent proportions. For example,brass is ccmposed of 7 parts ofcopper (Cu) lo 3 parts of zinc (Zn).

Answer these:

, a) What are the percentages of copper and zinc in brass?b) What are A and B in the chan?c) What is the ratio olcopper to zinc?

Now look at the charts and compiete the statements:

Sn 6% Zn 2o/o

compos!ttonof bronze

composlttonof lead solder

Norv drari, ii rthart to35 ilj cobalr (C.o). 65'l

d) Bronze is madeto 3 parts

parts ofe) Expressed as a _-, the com-

position isl copper __/,, tinzrna _

f) The ratio betwecn copper and theother metals is _.

g) Lead solder consists ol oftin to

-- of lead.

h) Lead and tin are ina ratio of.

up of I part ofof-to46

a)b)c)

What is tl.re ratio betu,een students ofstudents ol engineering ?

The ratio betv;een students ol science andengineering is 3:2. (three lo twoJ

science and I

stLldents olshorl' ihe composition oj. crrbalt stccl:i ilon (Fe)

81

Engi neeri ng

Exctmple

,l-J'

2. t,ook ai fhis tahle:

ll. Look at the diagranls andCorrect the false statements.

sa-l' rl'hether these staternents arc true or false.Abundaircc of lhe most common elements bv mass I

.lacrF

102030405060Temperature in degrees

Centrg rade

f) The solubility of copper sulphate and ammonia is inverselyproportional to the temperature ol the water.

g) -l-he warrner the water. the greaier tlie soluhility ol arnltoitia.ir) fhe coider the ivater, the less ihe solubility of'copper sulphatc.i) The relationship between temperature and solubilitv is nbt the

same for ammonia alld copper sulDhate.

Cr:ust Sea g,atcr Whole Eartlr ]"-*l ': :l:11' :1 .:1:r"l' '. l

iron 4(I 50

Oxvgen 22 28

Silicon I I -15

1"1;ignesiun 9

Nickel 3-6Caicium 12Aluminium I 2

l

I

Norv ansrver these questions:

a) Which elements colrstitute approxirnately 80 l{ of the Earth'scrust ?

b) What percentase of sea rvater do oxyger.r, h'vdrogen, and chlorineconstitute'l

c) Express the amounts of oxygen in the Earth's crust, in sea water.and the u hole Earth as a ratio.

d) Which element has a ratio 90:20:l in the whole Earth. in thecrust. and in sea u'ater?

e) Which eleinent has an approximate ratio ol 5:2 in the crust andin sea water?

f) Which element has a ratio of 85:l in tl're crust and sea rvater?g) In sea water compare the amount ol chlorine with (i) ox,vgen

(ii) bromine.lr) Cornpare the arrount oi iron in the whole Ear-tl.r with the an.iouni

oliron in the crus!.

3. Look at the table again and read the following passage:

Ox1'gen, silicon, aluminium and hydrogen together constituteapproximately 80% of the Earth's crust, sea and atmosphere.Nitrogen is the main ga,s in the air. but is not one of the most commonelements. liitrogen forms only a small percentage of the crust andoceans, and the mass of the atmosphere is negligible compared withthe total mass of the Earth.

Air is a mixture of gases. Its composition varies and de pends to a

larse extent on plants and animals which control the amounts ofoxygen and carbon dioxide by photosynthesis and respiration. Airusually also contains water vapour and dust.

Il the dust is removed, the approximate composition by volume isshown in the lollorving table:

a)b)

Aeceleration is directlv proportionalThe greater the pow.er of a plane'sceleration.

to force.engines,

Ory ge n

SiliconAluminiurrI ronCalciunrSodiumPotassiuml\{agnesiurnHvd rnoen

Titanium

Orr qen 9l[Jrdrogcn 5 7

Chlorinc 1

Sodium i

Magnesium 0'1Sulphur 0 08Calcium 0 04Potassium 0'04Bromine 0'01Carbon 0'003

the slower rts ac-

|t) 4

t-5 Ej.,iA.1

3,1 l

26:24 l

n.g l

0_sF - ma 15 secs

30 secs

45 secs 40 km/h

c)d)

Accelelation is inverseiv proportional to rnass ior a given torce.The relationship betrvecn mass and acceleration is thC sa're kinrlas that between lbrce and acceleration.The srnaller the rrass, the laster the acceleration.

bo-pb:<LOtg)

=O;ol-oa

r nn -,

vu r:

80

70

60

50

40

30

20

10

,rammonia (NH.)

copper sulpha:e (Cu SO")

,/

87

Now look at these alternative ways of expressing probabilities:

trnert gases (mostiy argon) 0 93 :.l,

NitrogenOx.yger.r

Carbon dioxide

c)d)e)f)

'7Q o/

2l ".r.,.

0.03','.

(extremely) ,[strong\(fairly) l. high jlffi')(

possibility that X will happen. I

I

0%

Now say whether these statements are true or lalse. Correct the falsestatements

1- smail cuantities of other gascs

Oxi,gen combines with metals to lorm oxides. In this way oxygellcan be renroved lrom a sample ol ail and the amount present in thesanple can be nieasured.

There is a/an

The(extremely)(fairly)

N{ake predictions like these, from the frequency diagram, about the possibilityol

a rainfall of 8 cm.l0 cm.6 cm.4 cm.

12 cm.more than 20 cm.less than I cm.more than 14 cm.- between 6 and l0 cm.between 1l and 15 cm.

Exantple: The possibility that the district will have a rainfall ofless than I cm is extremelv low.

(fairly fweak I(extremely) J low t

I slight fI remoteJ

no

possibiiitylprobabilityf ihar X wiii happen islikelihood J

100%f trish. It't'oie. J

f low. )J weak. t

I slight. IL remote,jnil. 0i(

a)b)

Nitrogen is one olthe most comlron elements in the earth.The mass of lhe atmosphere is small compared with the mass ofthe crust.T'he composition olthe atrnosphere is constant.Air normally contains only gases.

The inert gases.constitute approximately i I of the atmosphere.The inert gases include oxygen.

Look and read:

12345678

Rainfall in March (in centimetres)

This frequency diagram represents one month's average rainfall inone district over the past 50 years. It shows, for example, that thedistrict had a rainfall of approximately 8 cm 10 times. How often didit have a rainfall of 5 cm?

10

aeG

39 8c+oOr- 1GO

'iE 6lC tr

4

3

2

1

0

93 94

-'

pDu:fi

J

)

Section 2 Development

4. Look at this graph:

?.o

1.6

a4

o2

1 2 3 4 5 6 7 B 9 10 11 1213 14 15

Time elapsed (hours)

Failure rate

'I'his graph shows the lailure rate of compoltents produced ingiven lactory.

Look at these statements:

The lailure rate at the end of the first hour is approximately 1 i;.This means that ten out ol a thousanci components are liable to fallat the end of the first hour of operation.In other words. the chances of a component failing at the end ol the

, first hour of operation are one in a hundred.

Now say rr'hr:ther thc lollorving staternL'nls are true or laise. Cot'rect thr iaiscst:,. te mc n ts.

5. Read this:

In a given system the chances ol a component lailing alter the first

fir,e thousand hours are one in a thousand. During the next three

thousand hours the chances ol failure unilormly decrease until aiter

eight thousand hoUrs the chances are one in two thousand The

failure rate remains constant for the next lour thousand hours. Itthen enters the wearout period and the chances ol the component

lailing in the next three thousand hours increase uniformll' to one

in eight hundred.

No*'drarv a graph to plot the changes in laiiure rate as a percentage. l\4ake

the vertical uii, it.r. lailure rate and the horizontal axis the operating hours.

6. Look at this graPh:

18

.i

.Jr.:liS

! dir .!t

::.,),],L:'.'. ',)

grIt-S'l ^ 14

sa tzfc:10oa. 08I! oo

I

>\9flsl0)5 j-'D0)

-0

P;D'!.) )i .oDIi;

Irour ou1 ol a lhousand components are liable to lailol thc third hour ol opcrali'rrr.The chances ol a conponent lailing at lhe end ol theare one in thlee hur-rdrecl.The f ailure rate at the end ol the filth hour is approximatelr I 1;.Four componenls out of-a thousand are liable to Iail at lhe endol the fifih hour.Six components out of a thousand are iiabic to lail at the cnd oithe eleventh hour.The f ailure rate at the end of the thirteenth hour is approxin.rately'(] 8:iThe chances ol a component lailing athour are one irr a hundreci.Of ten thousand components produced,b1,the end of the filteenth hour.

upper limil

Component size distribution curve

A given machine has to produce components with the diameter

rvitl-rin the iimits 49'987 to 49'995mm. The graph above sho*'s the

distribution of the size ol the components'

[,ook at thesc examples:

The probabilil,r' of the machine producing a compcnent the diameterol which is rvithin thc range 49 99 I to 49992mm is lcrl ligl.The probabilrl-r'of the machine producing a component thc diamcterol which is within the range 49'992 to 49'994 mrn is high.The probobili 11' ol the machine producing a component the diame ter

of which is rvithin the range 49'994 to 49'995 mm is considerohie.The probabilill, of the machine producing a component the diamelerof which is within the range 49 995 to 49'996 mrn is lotr'.

The probabilrll' e; ,1.,. machine producing a component the diameterol which is greater than 50'00 mm is ni1.

I(.-t Aa"'1)

L

7

ll

!

)L

r) at thi 3nd

thirci noi:r

c)d)

b)

r)

h)

e)

sl thc end ol tire filtcenth

fi..'e hundred li'ouli fail

I

i

J