1978-04-29 — Page 30

頁二第張八第 日三廿月三年午戊馨

WAH KIU YAT PO

報日僑華

六期星

育教僑華

物理 (三十) 魯榮家

4 numerically)

#x

f 15 cm

PHYSICS (30)

Apply the mirror formula

1978

中學會考試題預習專欄

Answers to Revision Exercise (cont.)

x = 11.25

(ans.)

[6438, 4. Dale Beach,

5.(a) Let the frequency of the tuning fork he fills, the ori

ginal length of the wire is

.. (1)

where Thin” the tension of

the wire and n ja the mass

經濟與公共事務(三十)

·孔繁盛 ·

Economic and Fublic Affairs 30

Independent' Commission Against Corruption(ICAC)

The Independent Commis- sion Against Corruption is responsible to investigate. auspected corruption offen- ces, prevent corruption and promote higher social ethics. The Commissioner is directly responsible to the Governór,

It recru its its own staff and is financed from general reve-

nue.

The commission has threefunctional brances: operations, corruption pre- vention and community rela- tions.net

The commissioner is

advised by the Advisory. Committee on Corruption on policy matters relating to anti-corruption.

Under the Prevention of Bribery Ordinance, the Cor- rupt and Illegal Practices Ordinance and the ICAC Ord- inance, the Operations De- partment investigates alle- ged or suspected offences,

The Operation Target Committee, which is chaired by the commissioner and consists of citizens and senior public servants, re- ceives all reports of cor- ruption.

The Corruption Prevent- inn Department examines the procedures and practices of government departments and public bodies and reco- mmends changes in work methods so as to reduce the possibility of corruption. It also gives advices to help people eliminate cor- runt practices.

The department seeks in the long run to broades its scope of activity,and ref-` ines its methods or iden- tifying corruption opport- unities and devising prev- entive measures........

The Community Relatime Department is responsible to educate the public to fight against corruption. The long-term objective of the department is to foster greater civic aware- ness, faith in government and higher social ehtics. The department is guided by the Citizens' Advisory Com mittee on Community Relat- ions. The Department's activities include public information and education campaigns through the mass media; and personal contact with the public, individua- lly or in groups. A pro- gramme of Liasion talks and visits were made with diff- erent sectors of the comm- unity.

There is a Community Research Unit responsible for monitoring public atti- udes towards corruption and the impact of the commiss- ion's education programme.

An ICAC Complaints Committee was set up in December, 1977 to study complaints against the con- misadon,

On November 5, 1977, the Governor instructed the ICAC in future not to act on complaints or evidence relating to offences, com- mitted before January 1, 1977, except those who had already been interviewed, persons outside Hong Kong, or persons who had commited a crine 80 serious that

would be impossible to re-

frain from action.

育教僑華

per unit length of the wire If the length of the wire is increased by 1/50 of ita ori- ginal length, then its fund- amental frequency will

be lowered. Since five. benta.

per second can be heard

- 5 m

放

01

where l' is equal to lol

(1)

(2)

Ans

50

255 (Ans.)

the frequency of the fork is 2551. (b)(i) The graph of Lagainst

1/t is as follows

(11) Let v. and c be the velo- city of sound in air and the

end correction of the tube

respectively.

入

7(7)

Therefore, the graph of L against 1/f is a straight line

with slope v and y-intercept.

From the plotted graph,

Blope 85 ma

(6)(1)

Jv

(Ans.)

340 ms

intercept - 0.05m

0.05m (Ans.)

The image of AB is A B (15) From the graph,

-

AB

0.6 (ans.)

the magnification ». 0,5

(b) Since the image is enlar-

ged, therefore, the mirror

must be a concave mirror.

Case I Real image

· (Using Real-is-positive)

Wa

x

1 =

ex )

35 cm

Apply the mirror förmula. 2°

=

4

X

x = 18.75 (AnB.)

Case

: virtual image

Ana The object must be pla- ced 18,75 en from the mirror (for real image) or 11,25 cm. from the mirror(for virtual {nage).

(e)

Hence

日九廿月四年八七九一腊公年七十六國民華中育教僑華

Como fe of y

Note the eum,f. of each cell

must be less than that or

the driver cell.

order to use the gal- vanometer to measure a

1A, 8 Jow resistance stunt isconnected in. puura

allel with the galvanometer as shown in Figure he làw

0.998

across galvanometer pid, perosa shant

Let the angle of incid

ence hai by Snell's Lav

gin i sin r

- 1.5

sin

(a)

By Geometry

Substitute into (1)

sin

- 1.5

sini 0,4630:

i

(Ans.)

(ii) The critical

angle

(Ana,)

(1=0,01) x R

992

(ang.)

210

In Figure 15, there is.

no induced current,

(c) in Figure 17, the rod AW

will move to the left-he

shown in the figure.

Figure

In figure 18, tberg, 18

no force seting on the ean- ductor aB. (for the magnetic field and the current are in same direction) Therefore no motion is observed,.

(e) let the life time be T.

Since 1000

8000 =

ንጥ

(2)?

6 min.

= 2 millo

SUCTION C HECTRICITY

MAGNETISH & ATOMIC PHYSICS

7(a) When balanced the

of E is equal to the p.

across AX-

For the rauge 0-7V

is connected in series with the galvanometer.

p.d. across the combɔina ti-

0,01 x 41 +

For the range (~10V,- Hy is connected in series, with

the galvanometer, similarly, 0.00

9990 (ans.)

For the range 0-190V,. connected in series with

the galvanometer, hence

0,01 × (X + Hz).

· 15

99992 fans.) ()() Apply D

The correct operating voltage - (0.5)(40)

=20V

(ii) Power dissipated

育教僑華

學能推理練習專欄

智慧社主編

數字推理練習(十九)

Elenes

0.75

1.5V

(Ans)

1.5 (129) x (1

A 1m

Solve AX from the equation

AX 1 in

the balance is

(b) A safety high, resistance and shorting key abould. be

added to the circuit ng

shown below

·watery, high

driver cell

(e) Suppose cells Ej and Eg

are going to be compared, The circuit is as below:

Driver Cell

(^ns.)

(ii) lær the resistance of

the inserted resistor be Il

240. 40+ R

- 0.5

-(^ns,)

R = 4400

9(a)(i)

Apply

P

·

2000

100

(in.)

(ii) Since efficiency-

power from seconde 5%%100%

power from primary

1 x 12

4 x 100%

20% = 2401

whère: fm current from 240V.

16

A

0.0695X (Ann.)

(b) (n rigure 1), the murrenta through the wires are in the

same direction, the rods will

attract each other,

An figure 14, the currents -

through the wires are appraite

în direction, the roda wi)X

repel each other,

(e) in figure 15, the induced

current flows from B to A.

as shown in the figure below

motion

Index

Two

(Figure 15)

數字推理疎習一九

分數應用的推理

選出下列每題的正確答案,並在它的下面薹 一橫線。

1.若▲是由1至10的任何一個整數,下列五個

歎中那一個可能不是真分数?

A

B12

2.下列那一個分數不等於一?

87.5

D22 E

•Ag A05 CH

15 3.下列那一算式的值不等於12

A2X1

cut D}

EX2

4. 繩子一條長3米,它的儿子多少?下列

那一算式不對?

C3*X -

E

**-*

D3*X

5. ***# 三種鉛擎的價值等於一枝原子

*****

,三枝原干擎的價值是:

AEL BOL CIEL DIJA 633L

6.甲球的重量的球的重量是西球

的2倍,若甲球1個,乙球1個,丙球2 共重495克,丙球一個重:

P902 Q1102 R1322 S1802 T2642.

7. 波子一金綠色的信号,慢色的信号谷線

色的波子有14粒,撥色的有:

P4粒Q12粒 R24粒 $84粒 T294粒

8.空地一塊,用它的房子、 臺鐵花園,其

餘的空崖,若空置的地有200米、房子的面 積是:

P75**

·S 160**

马张先生去年加薪,

̇薪金比原來:

P100

10

Q85*2

R1202

T280*2

今年減薪通;他現在的

RATA

T'ho

1

100

10.'大明用去其存款之一,再用去其餘的ㄗㄨㄛˇ,這

餘18元;問下列那一项是不對的?

P大明原有40元

Q太明用去全部款项的通

民太明第一次肟去10元

S大明第二次所用去的款項較少。

̇T大明所餘的款項不是原來的一半。

**:0A OD OB OC SE OP

OR OR OP OS

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