頁二第張三第日十初月正年酉辛歷夏
1981
中學會考試題預習專欄
數
(十九)
明德出版社交長波提供資料
Mathematics (19)
C. P. Man
MILE & DALE PRESS LTD,
Exercise
Answer All questions in Section A and any six questions
s in Section B.
Section A-.
1. Factorize
a2(a-2b)-b3(b−2a)
The sum of the squares of four consecutive odd numbers is 596. What are the number?
5. A debt of $1000 bearing.
compound interest at 45% is to be repaid by 2 equal annual înstalments, the first payable one year. after the contraction of the debt, Find the amount of each instalment.
BC. (2)
B
In the figure, ZHAC ABL BC BD:DC = 1:4, find the ratio of AB:AC. (Geometry theorem need not be quoted when used.)
B
D
E C In the figure, ABC is an equalateral triangle, D, E are the mid-point of BC and DC respectively, find AE in terms of EC. (Geometry theorem need not be quoted when used.)
Two vertical poles 6m, 10m high stand on level": ground 5m apart on the East-West line; a fight rope connects their tops; when the sum is due South, the shadow of the shorter pole is 4m long. Find the length and the bearing of
the shadow cast by the
rope.
會總軍童港香
獎|章|
禮[頒|獎|公厅
津上,○道期
年九六
* 名譽券三種,歡迎各界友成。成
·香港童軍總會定十四日無
演項科,換物安分爲三元,五元及一百元 一會,將有遊戲讒位四十缀,換物攤位十個及一 午一時至五時假九龍培正中學行慈善換物 ..香港童軍九龍地域於十五(星期日)F
蒋挺,恭的宝蓝星家河財司合眾國手 三、獎助學金 林院設有多項獎助學金,几家近酒燃液松優良者可
一. 大專部:白文科中心、社工、哲敦、
華僑書院 春季招生
*章長::舔
做洲三三米
案花|道|埗
褙
八五八章:助南飲管25
四四季二
○座九三 金
五五四〇
五大二
章頒 得獎之築系共計一百二十三人, 四、校址——四九龍深水埗續拿第三0二至三○六號。
有茶點招待嘉賓,歡迎各界人士 獎禮 四人及金堂十人。典禮完畢後酸 分別爲鍋章六十九人,鎮四十
In the figure, ¿BACK-30 PIL AR and PKLAC. Prove
郭日僑華
WAH KIU YAT PO
六期星
日四十月二年一八九一公年十七國民華中
眘教僑華
area is bisected by a line XY parallel to the diameter AB, If ZAOX =
< prove
that
28
sin20o
20
=Z]IKP
thut: (a) ZM LOK.
(b) AP
14. If an A.P. and
added together, the sum of their first terms is b, of their second terms is -1,
of their third terms is If the first term of the 6.P. is twice the first tera of the AP. find the common difference and the
ratio, COMMOTI
15, A Line AB, 8cm long,
divided at. P. If AP = x cm, Find
(a) APB in terms of
(b) x such that Ap2+pr2
a minimum and
(c) the minimum value of
AP PB
In the figure, I is the in-centre of AABC and G. is the ex-centre of AABC described on BC. Prove that (a) B. G. C. I are concyclic (b) As ABI and AGC are
similar,
If (se¢A+1)(secB+1)( sec(+1) equals
(se¢Â¬1}{ secB−1){ sec(−1) and if all the angles are acute, prove that each expressions equal tanAtaußtanC.
7. If sine.
and is
acute, express Lane terms of».
8. Find a relation between x and y. when do not involve logarithm
21og(x+y) = log(8-y)+1.
Section B.
9. A fest tube consists of a
hollow cylindrical tube joined a hemisherical bowl of
the same internal radius. The whole tube holds 350cu.cm of water and the water in the cylindrical portion falls 1cm if 20c.c. of water are removed. Find the internal radius and the length of the cylindrical portion of the tube
10.
-C.
In the figure, ACB is a
semicircle, centre 0; its
院書皇英
日放開四週 蘿
觀參界各迎歡
期
(0) Į (b) If
11. An estate was bought by
man for $240000. He sold A of the estate at gain
20% and
and of it at a loss
of 15%. At what gain per
cent must be sell the
remainder as to make a
profit of 10% on the whole.
物理 (十九)
明德出版社番榮家提供資料
Physics (19)
W.K. Lo
Till & Dale Fress Ltd.
Exercise Ten
Magnetism, Electricity Atomic Physics
1.(a) Figure 1 show
potentiometer used to measure
the emf of an unknown cell E.
AB is a wire of length 1m, G
is a sensitive central zero-
galvanometer and the emf of
the driver cell is 24.
driver cell
2V | 1
Figure 1
(i) The galvanometer G reads
zero when the contact X
is 0.75m from A, what is
the enf of E?
If the 2V driver cell
has an internal resist-
ance of 1 ohm and wire
AB has a resistance of
9 ohm, where is the
balance point when a ?
ohm resistance is placed
in series with the 2V
battery?
(b) Fractically, it is easy to damage the galvanometer by
large current if contact x
is made on the wire AB far
from the balance point.
with the aid of diagrams,
suggest a method to pre-
vent from damaging the galvanometer.
(c) with the aid of diagrams,
explain how a potentio-
meter can be used to com-
pare the emf of two cells.
2. In figure 2, the internal
resistance of the 2y cell E
is negligible.
2V1 E
3.52
Figure 2
(a) Find the potential
difference across BD.
(b) If B and D are joined by
a copper wire, which way
does the current flow?. Why?
(c) If the 7 resistance is
replaced by a resistance
of R ohms, find the
resistance R such that
galvanometer shows no
deflection when it is
connected across BD
3.(a) A transformer steps down
from 240v to 12V with 1200 turns on the primary (1) Find the number of
turns on the second-
ary.
(11) If the efficiency
the transformer is
80% and the current
taken from the
secondary is 1A, find
the current taken
from the 240V supply,
(b) Figure 3 and figure
show two copper rods
lying in a horizontal
plane. Electric current
is flowing in each of the cases. What will happen in both cases.
insulator
英文校聯會會長譚萬鈞力申
尚望當局週詳考慮 始能全面照顧需求
HSEN EEN BEE(2)
初中教師
本校聘中一中二數學自然
及英文教師鲜履歷函九龍
牛頭角定業街48號
Cosmopolitan College
Quer Cotway Stengt fra vore Ontario Candid.
加拿大
多倫多
哥詩姆書院
A. 招聘本年2,6,9月份·第11,12,13班大學預科新生
B. 歡迎香港及澳門F.3.F.6學生申請報名,協助辦理簽證
C. 畢業生可直接升入加拿大著名大學數十間
D. 駐巷辦處地址:尖沙咀漆咸道33-35號友聯大廈7G室
E. :3-669468 3-676769
Secretarial Training in U.K.
華專秘朧
3 terms, Diploma Course in Pitmans, L.C.C..
R.S.A. Examinations. Accomodation provided. Mrs. Hunter
14 Cavendish Heights.
Jardines Lookout,
Hong Kong.
也加 簿用,以協助解决社會的需求。
公私教育機構必須結合
Figure 4
(c) Figure 5 and figure 6
shows a copper rod AB is rolled in the indicated
direction, what is the
direction of the induced
current in each case?
mutati
red
Motion
Figure
Figure 6 (d). Figure 7 and figure 8
show a copper rod AB is placed on two metal rods and current is flowing on each of the cases, what the direction of motion
of the rod AB in each
Case?
Figure 7
Figure 8
الأمد
N
A radioactive element is
examined by means of a G-M
tube connected to a scalar.
The count rate drops from 8000 per minute to 1000
per minute in 6 minutes.
(a) What is the half
period of the
(b) when will the count
rate drop to 250
minute?
私
·地點上在
氮各有香
#TA 港的士
教
育
DRA
Page 10Page 11