REFERENCE LIBRARY
CF
育轂僑華頁三第張六第 日八廿月三年己屣 WAH KID VAT PO
1969 ?
荪日僑華
物理科 (廿八)
陸永熾
PHYSICS (28))
(a) When a thermometer has been made, 2 nas TO a scale on it, making on it a suitable zero mark and a suitable size for the temperature units or degrees. The size of degree ia settled by choosing two fixed pointë, temperatures which is known to
, bie
constant,
and dividing the interval between them into parts or degrees. The chosen fixed points are the temperature of pure melting ice and the temperature of steam coming from water boiling: under standard atmospheric pressure.
In Celsius scale centigrade scale, the rower fixed point is 0°C and the upper fixed point 19. 100 0.
In Fahrenheit scale, the lower fixed goint 32°F and the upper fixed point is 212 F
(b) Formula for conversion of Fahrenheit to
Centigrade.
180
32 180
+
papers immediately before it is put into the calorimeter. 7
Stirring continuously when surriciently ice. added and when all ice is melted a final
melted
temperature, steady, one, will be brought to Beveral degrees below the room temperature.
It la purposely in this experiment to arrange that the calorimeter 18 for approximately half the time abové room temperature and for the remainder of the tame the same number of degrees below room temperature. As a result the heat gains and losses of calorimeter from and to the surroundings cancel each other out
(d) Thermal capacity of tray = 25 cal per
Mass of water in the tray - 400 gm.
Cooling rate of the re frigerator
(400 + 25)(255)/10 cal/man
4252
850 cal./min.
If the tray and its content loses heat at the rate of 10 cal. per sec. from the moment of freezing, to convert 400 gm. of ice, water
0 degree C to los, it takes
400 x 80/10
400 z 8 sec.
53 min. 20 sec,
三期星
日四十月五年九六九一融公年八十五國民超
中中會考特別科目考試
(RE)KURE
今日開始舉行
九四十一個試場舉行 教署經將「 普通科目定六月二日開始 分在港外,每題均須另莨作答
考試須知」分各校
打
校行日
- 一九六九年香£巾 亦不得將試場所備之對
之四十一個試塲內舉行 六月十一日止,在指定
那科目考試, 將至六月,地點及考試時間。與。. 共有十七項,亦由會交卷、品、紙張及封面 耳
二時至五時,此等的很黑所選考科目之队,經內,考生均不得離開離開試事。 會考之「考生須知」:「將任何宮,對數表、及試場名稱寫在其雅之十三、試戶紙療
十七日始全部考究。但考生須於屈科 六、考試邁爾市, 特許時間內者入 北京六月二日開始,一試場,並依照編號就座面有角,以備查開。3 項規定辦晏後,則果手 故育考之普通科考試,考試開始前十分到米 考生須將考試證在東| 開第五項),照第十一 蘗科之堂取實習(下午:一、考試前考生為十分鐘及完裕前十五分,借准許離座,方可 四、考生絕對不得一始 - 凇生須將畫編號 可傑安
肉牛至十一路),及工 鄭格。一進入狀線,在開考後三縣,有熱捕壇經號,腳 三、考生不得參加 南主任監考攝報告。; 有無作答,均應城
做剪(設計)(上午九 試成讀- 我被取消考就三十分肥往,考生不得,然後檢查所有作容之紙,紙由原校校長轉 開考,科目爲工棠科之有慰路,可能影响其五,每科考試開始,我的緊緊幫於試卷內,一撕業 七,在毎科考試開目名稱及考生醬,才 -未能出示准考證者, 監考試然不論
| ''' 十二、考生如擬於
未考
拭,作答(包括
業學院
一 用過之紙關,均應在拍
where C is the reading in the centigrade
scale.
is the reading in the Fahrenheit Bcale
(a) Home-made thermometer
L.P.P. U.F.P.
20 degrees
80 degrées
60
(a)
Centigrade thermometer
zero degree
100 degrees
where X is the reading of the thermometer
C is the reading of a centigrade
thermometer -
(1) When the centigrade thermometer reads 5010-
X
20
60
X 50
(11) When the thermometer reads 56 degrees
-56-20-100
60
10 z 36
-60
Ans. (1) The reading on the thermometer 19 50.
(ii) When the reading of the thermometer is
56 the corresponding temperature in "centigrade degree in 60 dag. C
10
203-40
questions for.
week:
6. (a) What is meant by critical angle and total
internal reflection?
(b)
·(0)
Draw diagrama in illustration of your answer.
Can total internal reflection be obtained when. light passes: (1 from water to air; (2) from air to glassi (3) from glass to water?
8
Anglass block is placed on a plane mirror, án objøor 0 is situated above the glaze block, Of represents one of the rays incident from U onto the blook, Complete, the diagram and state what oba srvation you may have when looking from the top..
The diagran shows a semi-circular block of glass, refractive index - 1.5, with rays 10, 20 and CO insident in the glass at different angles, The ray BO is inäident at the" critical angle.
(1) Show what happens at U to each of thạ
成須秘宜者试能忍常形 用科六、陪由、圖、水表
在自十歲內人十?題十。靠、十一、考生釘 具色 校 前後七取外答六鑊有五,尺朗四上帶生自波
刊敎 再按函瓜或 生湿生形露生翻巠携 第在育
∴強考本會資助您不必尺,烤或鋪紅酒等影
·其他如 水筆
生食老格,圖約彩如須·及得俄白及、理、 in則考事。進在 抄圖有圖准覡槪長綠科均板繪率器 (接第六張第二页)
一九六九年中文学會考試題預習。
(IPA)
(1) For each of the following find a MAN
meaning IN THE PASSAGE:
(a) wrong
(b) scenery.
up-to-date
(d) stream (e) made small
(f) are inclined
(g) taking place
(h) süre
(i) energetic
·王淑方。
of similar
(2) Name three places that have been reclaimed from the
.sea,
(3) Why is the airport runway so long?
(4) What does a look at the landscape of Hong Kong today tell us about men's engineering ability?
(5) Why is there an incessant flow of traffic along the
waterfront?. '
(6) What are the two main reasons why it is necessary
for Hong Kong to reclaim more and more land?
((7) Why would the writer not be surprised if there were soon to be another park like the Victoria Park?
(#)
20 HOD 10:20 30
10 20 30 45
S.fal when we heat a piece of metal violently, it
will turn into liquid forms This is yelting.
In melting the temperature keeps constant at its pelting point will it changes its states. Heat is used up entirely to change the states inatead of raising its temperature. The heat energy used up is known as the latent heat. Latent heat of fusion of a metal is the quantity of heat required to convert univ mass of the substance from the solid metal to liquid metal without change of temperature.
(b) Beat absorbed by the ice in melting.
- 4.55 cal. (where is the latent heat of
fusion of ice):
Heat absorbed by the ice water.
- 4.5(16-0) cal
Total heat absorbed = 4.5(L+ 16) cal.
Heat given, out by water - 80 x (20
Heat given out by calorimeter
– 100 x 0.1 x (20 - 16) cal.
16) cal.
Total heat given out (80+ 10)(2016) cal. Heat lost heat gain
(80
90
+ 10)(2016) - 4.21* + ***
4 4.5(1 + 16)
L 16 - 90 x 4/4.5
T.
64
From this experiment the value of Latent heat of fusion of ice 10 found to be 64 qal, per
(o) Ice should be dried carefully befor
transferring into the calorimeter. A single grameof water clinging to the ice will Introduce 80 calories in addition to what; actually exist in the heat lost.
The drying is done wrapping loe with filter,
three rays.
(hi) Describe the brightness of raye in the
diagram of your answer.
Calculate the critical angle. Calculate the angle of refraction of the incident ray AO.
d) 4 concava mirror is sometimes used by ... a.
dentist as a magnifying mirror. Explain with a ray diagram how this is done.
To(a)
The above shown a small object D in front se a converging lana L, with a plane mirror K behind the lens. Hays such as AB are incident normally on . (1) Through which point to the rays reflected by # pass? (11) What do you know about the distance 0 to L? Explain your anavaz..
(b) Draw a labelled diagram of the eye.
Explain the meaning of accommodation and least distance of dietinot vision.
What is one advantage of the possession OF SWO eyed?
(c) Calculate the height at walon a 160 a.p. point
source of light must be hung above a desk in order that it should give an intensity of illumination of 5 foot, candles at a point is the desk below the lamp.
if a plane mirror ware to be placed horizontally 1 ft. above this lamp, calculate the new intensity of illumination at the same point on the desk, assuming that the mirror reflects all the light falling on it
8.(a) What conditions are required to produce
resonance of sound in a hollow container? Gave a practical everyday example of a usa made of this effect.
(b) Describe, with the aid of a suitable diagram,
an experiment union uses. a resonance' tube, open at one end, and a tuning fork of knowm frequency, to measure the velocity of sound in air at room temperature.
Show how the required velocity is calculateu from the observation made.
(c) A taut string has a length or 100 on and a tension of 2 kgm, and the nate produced by plucking is 400 oyales per suo. What note is obtained when: (1) the tension in decreased to 0.5 kg.) (ii) a bridge is then placed 40 am. from one end and the middle of this portion of the string is plucked. In the latter case, what is the frequency of the first overtons which may be obtained?
(d) The question below require only very brief
descriptions, shortened wherever
the use of diagrams,
possible by
(1) How can it be shown that sound will not pass
through a vacuum?
(11) How could it be shown that sound obeys the
same laws of reflection as light?.
iii) What conditions are necessary for two
sound waves; travelling in the same direction, to cancel each other and give." Bilence?
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