貞二第張七第
日九十月一十年卯丁麿夏 WAH KIU YAT PO
報日僑華
五期星
年七十七國民華中
日八月一年八八九一曆公年七十七國民華中 育教刊特節蹈舞
小學低年級甲級獎:樂歡。
中西方舞得爭級獎之西班牙舞(上)及意大利手巾舞八下)。
小學低年級甲級獎:拍手舞。
中學甲級獎:雲雨精
中甲級獎:紅花五地開
利舞〔全宛)及匈牙利舞八李城璧 中學組西方舞得甲級獎之 匈牙
【由上至下)。
認
台美貨櫃航運糾紛
小學高年級甲級獎: 維吾爾的春天
小學高年級甲級獎:高原上的春天
atome and the
tube and after.
black
centrifuge, the
| powder
height of the
precipitate was
cone.
white
powder
B
Cheating MaHCD, Water
aqueous
3
green
aqueuns NaOH
Ert. 11
blue
tinn
for Cert. Exam. (1988)
PHYSICS (15)
1988中學會考
試題預習專欄
. . : .
化學(十五)
measured. The results
were platted, on a graph paper as slove
below.
【特訊〕日內上獲得的欧洲空中 ——四〇〇度是爲前世界上打貨最多的 一巴士公司公布的最新預測數字,今后,唔氣式客機,約二千架,然而,由法 一萬多國:聆邦德国,英國和西班牙聯合制
bluish-
Relative height of
MILL & DALE PRESS.
(1)
nie
I.
十一
十二卷5
陳要造的A二二〇型主张就良,總航一百五十至三百人。主要貌爭對手是落
需要兪爲一千五百架,部爭將涉及上海天利博總大 兩類微。第一羗属于「小一大型」.. -织航里程約八千英里-戴客摄缮一
第三個陌或是大型遠程客战,市一煜祥達鹣杬三
勝激烈的角逐。
羅比原來用更大 歐空中巴士公司公布預測數字
今後二十年空还盘
【倍總南碗五千億美元,这一前景預示 系銃的新型飛機, :下三個因素:痴縣航空遯钢協會估計,正以油咄逛人的攻勢威脅美國飛機:宜,迄今收到的訂單已超過MD午 ↑莉歐美在世界客被市懋上進行一更·梁程三千五百英里 -有一百五十舞座. 道公司的MÔ十1型和將于一九八五 空中巴士公司的估闭考慮到了以便用,但迄今已收到舒敬四百汁龙架 空中客盘」。由于A三四油價格 位。A三二门型雕秦今年三月才没入一年投沁使用的實髗遠程A三四〇型一市
1
紐約
美埏
小學低年級組括優異獎及編舞獎之拍拳舞
Sentral atom.
小理(十五
明瀉出版社
MILL & DALE PRESS
Revision Exercises
M.A. V.R.
3. The V8. of a
Some comp
aachinec
(A) Lever
compound machine
(a combination of twa or
more
simple machines) is the product of the .. of the indi imple
(B) Screw jnck
V.R.
P
(F) Wheel and axle
friction
480-(140x2)
= 200 J
Exhalp 2:
(ADB.)
As shown in the figure, e compound machine conniata of a 300 inclined plane and a windłaga, The. radius of the cylindrical. drum r is . n. The radius) of the hundle a in 1.2 m.
V
洛杉磯三津市
西北太平洋
西北太平洋紅彩十二
·西南太平洋紐約十三大
十日一輝隆
十日,小信
+-M
地中海 地中海
欧洲
欧洲 歐洲
欧洲: 地中海 無鄰 纸洲
十二特 十二林
十三利達
新西蘭 澳洲
十五
澳洲 澳洲 弗里亞特蘭
新畿內亞
澳洲:
憾迈 三川新 十三、太古 十三選一礽
中東线
紅海
̇科倫坡印度
十月新 德拉斯卡拉奇肃罚十二海運 瓶打
十二 十二、糖 ̇統 二林
阿拉伯灣 思德 拉斯
谷
谷
機
十日水稻 沙巴山打根斗湖千四國光
曼谷
榮爷...
汶萊古诗缺巫
十日,海陞 生日國光
烏尼拉宿
̇十一、扫
新加坡:
费安
新加坡
SK
十一海险
十二、招商局
新加坡曼谷巴生十二馬士基
十字
·
釜山麵
大連
山
日本菇隆高雄
高雄
千日
十日港興
釜山
上海
上海
海口
汕頭聯門
高雄基隆日本:
:天津
上海
高雄
DANT.
Revision Exercises
for
Cert. Exam.(1988)
CHEMISTRY (15)
Question 22
The following results were obtained of an
organic compound Z:-
0.37 g of 2, an complete combustina, gave 48 cm of carbon dioxide,
measured at o.t.pi
and 0.45 g of water vapour..
II. 1,85 g of Z. when
vaponrized, occured.
a volume of 500 ca",
measured at-s.t.p.
III.0 adding a piece of l
sodium to compound Zi
a colourless gap Xia
evolved; which gave:a
"popsonid on apply-
ing flame..to it..
IV, Acidified potassium
dichromate turned
· from orange" to grean
og prolonged heating
with compound 2.
(a) Vaing the results in
I, try to calculate
its empirical
-farmula-
(b) Using the results in IT, try to calculate ita relative
molecular mass.
(c) Hence, or otherwis句。
determine it
molecular formula, (d) Uing, the results in
III and TV, state the
homologous series in
which compoundㄌ.
could be placed.
(e) Write down all. the
possible structures
of and name them
according to the
TUPAC system.
(1) Write an equation of ita complete combus- tion in oxygen.
(g) What is the minimum.
volume of oxygen,
measured at St.P,
required for burning
completely 7.4g of
question 23
(a) A set of 10 teat-
tubes of uniform
bore; each containing.
2 cm of 0.5 M
solution of a
metallic chloride,
had varying
quantities of 1.0 M
silver nitrate
solution added to
them separately. A
white precipitate was,
formed in each text....
equation of the formation of the precipitate.
(ii) What does the flat
portion of the graph indicate to you? (iii)How many moles of
metallic uloride are
contained in 2 cm3
5 solution?
at is the volume OT10 M silver artrate just enough torrecipitate all chloride ions? Heme calculate the amount of chloride
the
ions in 2 on the metalliu gigid aolution: (v) How many roles
chloride ions a
contained in one
wole of me Lellin chloride
(vi) What is the most
probable number of
·charge on a metal 高?
(vii)Using X. As the
symbol of the metal, write down the
formula of its sulphate.
(b) Daacrive briefly a
chemical test which would distinguish each of the following pairs of aubntances. The results of the teet on both substances of each puar should be clearly indicated. (i) Two aqueous
solutions, one of. which contains iodide ions and the other chloride fona.
(ii) Two solids, one of
which is sodium aulphate and the uther awmOVÍ UM sulphate.
(iii)Two black solida,
one of which is copper(II) oxide and the other carbon powder.
(iv). Two gnaca, one af
which is propene and the other propane.
(v) Two liquida, one of
which is ethanol and the other ethanoio acid,
Question 24.
{a}" A series of reactions
on a metal A and its
compounds is
yummarized in the
following 'block
diagram:
A colourless, pungant ges G is also obtained when A is heated with cone, HySUy. The gee G turns acidified potassium dichromate green from orange. D could dissolve into aqueous ummonia solution to form a deep-blue solution.
(i) Identify and name
the substances
A. H, C, D, E end Frespectively
(II) What is the gan G?
Write on equation of each of the following reactions. (1) A→B (2) C
D
(3), D-
(4) C →E
(5) E
Hase two gases which fears¶tely
civert to under sai tare condit (r) Write an equation
the conversion of ps to A, using either of the gase you have suggested in (iv).
(vi) Write an equation of the reaction between
D and aqueous armenia solution.
(b) W, X, Y and Z are the
elements in the same period, hut is the grupa IV, V, VI and VII respectively, of the Periodic Table.. All of then can form
stable hydrides with
· hydrogen under suitable conditions. (i) Write down the
molecular formulaė of these four hydrides.. (ii) How many bonded. pair(s) arid lowe pair(s) of electrons around the central atom in each of the hydridea.
(iii)Using the electron pair repulsion theory", draw. diagrams to show the moet probable 3- dimensional arrange- menta of the atoms in each of the hydrides,
(iv) Siste the shape of
the molecules of.
cuch of the hydrides.
(v) arrange the hydrides
in the ascending
order of the angle.
formed by the bonds The tween hydrogen
4.9 Machine
A machine is a device by means of which force (celled offort) applied at one point can be used to overcome another force (called load) at some other point.
The force which is applied to the machine is called the effort (2) and the force exerted by the machine ia called the load (1).
The mechanical advantage (M.A.), of a machine is defined as the ratio of the load to the effort,
..
The velocity ratio (V.R.) of a machine ia defined as the ratio of the distance mod fort
the same time.
V.R."
The efficiency(x) of
a machine is the ratio of useful work put our from the.anchine to the work put into the anchine.
'e
Taeful outpat,
Fark Input.
100%
Useful output power100%
Input power
L-41
M.A
V.n.
1
For n (perfect machine, e-1(1.e. 100%). In order worda for an ideal machine, no energy is wusted, the efficiency is 100% aid thus MAYR
Note: 1. Pive VR. can be
determined by considering the geometry o猄 arrangement of. the macbing, but the M.A. cad be found by experi- ments only, ar
from the value of Y.R. and
efficiency.
2. Practically,
十一
釜山
一,發
日本
大榮
̇山
港脚
高雄
招商局
效廣法刊明香
本
刊告律登令港月九報
力廣龐讀印柯必社必學必家必工
上海
南非 西
-非
非
日日二三
「新馬大亞
物之性有指政三三〉强告大者刷式有團讀生備庭覽商
有實關定府日叁在
V.K.
Effort arm
-
Loud arm
(B) Inclined plane
V.R.
C
Laweight
Bine
(C) Single pulley
(i) fixed pull
V.B. 1
V.R.
Movable pulley
(D) Block and Tackle ·
system
V.R. D
le hydraulic prena
"AE = "L'AL
Load
area
Jarea
fluid
V.R. =
d.
"L
A
uple 1: OOOBA pulley system
where is the number
of strings supporting the lover (movable)
block.
100%
efficiency
The efficiency is smaller then due to the effect of friction, weight of pulleys and weight of the string. As the Load increases, the effect of the above factors beconei comparatively smell,
therefore the efficiency
is much smaller than unity for small load end tende to 100%great load.
consisting of 2 fixed and 2 nuvable pulley is used te raise a 72 kg losd.os. atown in the figure. The efficiency of the ayatem ia 75%.
(a) Find the effort
required to raise the weight steadily,
(b) If the movable pulley
block weights 140N, find the work done against friction only in raising the lood 22 0.
Sulution:
→ 3
E
(a) Find the V.R. of the
Machine
(b) lf a man has to exert
an effort of 20N to the handle so as to pull the block of maxam 18 kg up the inclined plane steadily, find the efficiency of the machine.
(c) In addition, if the
black moves 20 m along the incline, in 30s, find the power wasted due to friction. (Take g = 10 ma
(a) V.R. of the machine.
=(.. of the inclined.
plane)x(V.h. of the vindlass)
27R
ain30
1.2
= 12
(Aws.)
(18)(10)
叫
=
G
efficiency
=
M.A.
1.4 x 100%
駭
12
x 1004
75%
(a) V.R.- 4
M.A. = V.R, x 75%
Load weight of the (e) The vertical distance
travelted by the block
block
= 72x10
720 N
MAL 3
- 20sin30" =10m
(ad)
720
;
= 240 N
(Ans.)
(b) Work dune by the
effort in ruising the Load 2 a
=5.d
=240x(2x4)
-19207
Work wasted
- 1920x(1-75%). = 480J
Work Jane în raising the lower block 2m) (work done against:
friction)
(weight of the lower.
block x 2m) + (work
dane against friction)
(14)x2) + (vork done
against friction) Workdone against
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The displacement of
the effort dgadyXY.R.
2 (10)x(12)
̇=120ml®
(Note: 20xV.R.}.
Work done by the effort in moving the block for 20.1.es, wark done
by E in raising the block through a vertical" height 10m)
ExLE
* 20x120
24003
Work done due to
friction
2400x(1-75%)
600 J
Power wasted due to friction
600 J
-30 1
20 W
(Aus..)
全經包專新歷六一創 僑濟羅刊聞史月九刊 稱報萬豐翔悠五二在 許導有富實久日五於
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