PHYSICS FORM 5 PAPER 3 FIRST SEMESTER EXAMINATION 2017 SMK GREEN ROAD 2 hour 30 minutes NAME: ………………………………………………….
CLASS: ……………
The following information may be useful. The symbols have their usual meaning.
1.
a=
v-u t
2 2 2. v = u + 2as
1 s = ut + at 2 2 3.
pV = 14. T Constant
24. V = IR
4. Momentum = mv 5. F = ma
energy 17. Power, P = time
8. Elastic potential 1 Fx energy = 2 m r= V 9. 10. Pressure,
P=
F A
11. Pressure, P = h r g 12. Heat, Q = mcq
18.
25. Power, P = IV Sec
16. v = f l
1 Kinetic energy = at 2 2 7. Gravitational potentioal energy = mgh
ax D
23.
2 15. E = mc
6.
l=
13. Heat, Q = mL
N s Vs = N p Vp
A
19.
I sVs �100 I pV p
Efficiency =
1 1 1 = + 20. f u v 21.
n=
sin i sin r
C
Full Marks 4
2
5
3
6
4
7
5
8
6
8
7
10
8
12
9
20
10
20
11
20
12
20
Marks
Total
real depth n= apparent depth 22. n=
B
Questi on 1
dalam nyata dalam ketara
26. Q = It 27. E = I ( R + r ) -2 28. g =10 m s 8 -1 29. c = 3.0 �10 m s
1(a) 1 1
Section A [60 marks] Answer all question in this section. 1.
Diagram below shows an instrument to measure a physical quantity.
20
10
0
10
20 30
30 35
35
A (a) What is the meaning of physical quantity? [1 mark] (b)
Based on diagram above (i) State the type of error caused by the instrument. [1 mark] (ii) Name the measurement unit reads by the instrument. [1 mark]
(c)
Complete the following sentence by ticking (√) the correct word. The reading taken using this instrument should be corrected by Subtracting the reading with the error reading.
Adding the reading to the error reading. [1 mark]
2.
Diagram (a) and diagram (b) show two actions on landing activity by two athletes.
Diagram (a) (a)
Diagram (b)
Both athletes jumped from the same height and fall on the same ground. (i) Name the force that causes the athlete to fall down.
[1 mark] (ii) State the name of the phenomenon given to (a)(i). [1 mark] (b)
(i)
Compare the impact on the athletes during the landing . [1 mark]
(ii) Explain your answer in (b)(i).
[2 marks]
3. A metal block of mass 500 g is heated in a boiling water of temperature 100°C. The metal is then quickly transferred into 250 g of water at 13°C in a polystyrene cup as shown in Diagram 3.1. The moment the metal is in the water, time and temperature are recorded at 20 seconds interval. The temperature-time graph of the water is plotted as shown in Diagram 3.2. (Given specific heat capacity of water = 4200 J kg–1 °C–1.)
Diagram 3.1
(a)
Diagram 3.2 (i) What is meant by thermal equilibrium? _________________________________________ _________________________________________ [2 marks] (ii) From the graph in Diagram 3.2, what is the temperature when thermal equilibrium is achieved? _________________________________________ [1 mark /]
(b) Calculate the heat absorbed by the water in the cup when the thermal equilibrium is achieved.
[2 marks] (c) Calculate the specific heat capacity of the metal block.
[2 marks] (d) State one assumption made in your calculation in 3(c). ______________________________________________ [1 mark]
4.
Rajah di bawah menunjukkan satu sinar cahaya bergerak dari udara ke dalam air.
Diagram below shows a ray of light entering from air into water. Biasa Normal Air
Air Water
(a)
(i)
Bandingkan laju cahaya dalam air dengan laju cahaya dalam udara. Compare the speed of light in water with the speed of light in air. [1 markah] [1 mark]
(ii)
Jika air digantikan dengan cecair Y dengan lebih tumpat dari air, nyatakan perubahan kepada arah pembengkokkan cahaya dalam cecair Y. If the water replace with liquid Y which is denser than water, state the change in direction of bending of light in the liquid Y. [1 markah] [1 mark]
(iii) Namakan fenomena yang ditunjukkan dalam Rajah. Name the phenomenon shown in Diagram. [1 markah] [1 mark] Rajah di bawah menunjukkan sekeping duit syiling yang berada pada dasar sebuah bikar yang mengandungi cecair Z dengan kedalaman 15 cm. Pemerhati mendapati imej duit syiling kelihatan berada 4 cm dari dasar bikar. Diagram below shows a coin at the base of the beaker which contains a liquid Z with the depth of 15 cm. The observer found the image of the coin appears to be 4 cm from the base of the beaker.
Observer Pemerhati
15 cm
Cecair Z Liquid Z Imej bagi duit syiling Image of the coin Duit syiling Coin
(b)
Hitungkan indeks biasan bagi cecair Z tersebut. Calculate the refractive index of the liquid Z. [2 markah] [2 mark]
(c)
Cecair Z itu kemudiannya digantikan dengan cecair yang kurang tumpat. The liquid Z is replace with a less dense liquid. (i)
Apakah yang berlaku kepada imej duit syiling itu? What happens to the image of the coin? [1 markah] [1 mark]
(ii)
Berikan satu sebab bagi jawapan anda dalam (c)(i) berdasarkan konsep dalam ketara. Give one reason for your answer in (c)(i) based on the concept of apparent depth.
[1 markah] [1 mark]
5 Figure A and B show two identical boxes P and Q on a frictionless surface, each of mass (a) 8 kg. Each is being acted on by two forces of 17 N and 6 N.
(i)
Explain what is meant by acceleration.
[2 marks]
(ii) Determine the resultant force acting on P in Figure A and Q in Figure B. [4 marks] (iii) State the relationship between resultant force and acceleration of a body when mass is constant. (iv) Determine the acceleration of P and Q.
[2 marks] [4 marks]
6. Diagram 5 shows headlamps circuit of a car. Rajah 5 menunjukkan litar lampu hadapan sebuah kereta.
Diagram 5 Rajah 5
A high beam bulb, H are labelled ’12 V, 36 W’ and a low beam bulb, L are labelled ’12 V, 24 W’. Mentol ‘lampu tinggi’, H berlabel ‘12V, 36W dan mentol ‘lampu rendah’, L berlabel ‘12 V , 24 W’ (a)
(i)
Underline the correct answer in the bracket to complete the sentence below. Garis jawapan yang betul dalam kurungan untuk melengkapkan ayat di bawah The bulb in Diagram 5 are connected in (series, parallel). Mentol-mentol dalam Rajah 5 disambung secara (siri, selari).
[1 mark] [1 markah]
(ii)
What will happen to bulbs H if bulbs L blows? Apakah yang berlaku kepada mentol H jika mentol L terbakar?
……………………………………………………………………………
[1 mark] [1 markah]
For Examiner’s Use
(b) Both of the bulbs H are in Diagram 5 is labelled ‘12V, 36 W’. Kedua-dua mentol H dalam Rajah 5 berlabel ‘12V, 36 W’.’ (i)
What is meant by ‘12V, 36 W’? Apakah yang dimaksudkan dengan ‘‘12V, 36 W’?
…………………………………………………………………………… [ 1mark] [1 markah] (ii)
Calculate the current in the circuit when one bulb L is lit. Hitung arus dalam litar bila satu mentol L dinyalakan.
2
[ 1mark] [1 markah] (iii)
Calculate the total resistance of the circuit when all the bulbs are lit.
Hitung jumlah rintangan dalam litar itu apabila semua mentol dinyalakan.
[3 mark] [3 markah] (c)
4(c)
How can the bulbs be connected to increase the total resistance of the circuit? Bagaimanakah mentol-mentol itu boleh disambung untuk menambah jumlah rintangan bagi litar itu?
…………………………………………………………………………………... [1 mark] [1 markah]
7. (a) Diagrams A shows the parallel rays of light directed towards the concave mirrors, P and Q. In each diagram, C is the centre of curvature, CM is the radius of curvature of the mirror and F is the focal point of the lens.
(i)
What is meant by centre of curvature?
[1 mark]
(ii) Using to Diagrams A and B, compare the curvature P and Q and the effects on reflected rays. State the relationship between the curvature [5 marks] of the mirrors and their focal lengths. (c) Diagram C shows a girl standing in front of a concave mirror. The image formed in the mirror is virtual image and bigger than original size.
Explain what happens to the image if (i) the girl moves backwards 2 m (the focal length is 0.80 m), (ii) the concave mirror replaced with convex mirror. You may use the diagrams to illustrate your answer.
[4 marks]
(d) You are given two lenses of plane mirrors measuring 4 cm × 5 cm and a long cardboard tube to make a periscope. (i) Using the plane mirrors and other materials, describe how you would make the
(ii) Explain why the images observed through the periscope using plane mirrors are not very clear. (iii) Suggest modification that can de made to the periscope to produce clearer and bigger images. [10 marks]
8 Diagram 8 shows a hydraulic system. The small piston and the big piston have crosssectional area of 0.15 m2 and 0.5 m2 respectively.
Diagram 8 (i)
A force of 45 N is used to press the small piston downwards. (a) Calculate the pressure on the small piston.
[2 marks]
(ii) the maximum mass, m which can be lifted by the force of 45 N. (Assume that the mass of small piston and the big piston can be ignored) jisim maksimum, m yang boleh diangkat oleh daya 45 N itu.
[3 marks] (b)
Name the principle used in your calculation.
[1 mark] (c) (i) The small piston moves 10 cm downwards when it is being pressed. What is the distance, h moved by the big piston?
[3 marks] (ii)
State one assumption you have made in your calculation.
[1 mark] (d)
Various force, F are exerted on the small piston. Sketch a graph of h
against F. [2 marks] Bahagian B Section B [20 markah] [20 marks] Jawab mana-mana satu soalan daripada bahagian ini. Answer any one question from this question. 9. Figure 9.1(a) shows a boy pouring hot coffee into a cup. The hand of the boy is not scalded by the coffee droplets that are spattered from the kettle. Figure 9.1.(b) shows hot coffee spilling over and getting onto his hand and his hand gets scalded because of the heat capacity in it. Rajah 9.(1)(a) menunjukkan seorangudak lelaki sedang menuang kopi ke dalam cawan Tangan budak tersebut tidak melecur apabila terpercikair kopi yang panas itu.. Rajah 9.1(b) menunjukkan kopi panas tertumpah ke atas tangannya dan tangannya melecur kerana terdapat muatan haba di dalamnya. a) What is meant by heat capacity? Apakah maksud muatan haba
( 1 mark )
b) Using diagrams 9.1(a) and 9.1(b) , compare the situations , when the coffee droplets spatters on his hand and when the hot coffee from the kettle spills onto his hand. Menggunakan rajah 9.1(a) dan 9.1(b) bandingkan situasi apabila titik-titik air kopi mengenai tangan budak tersebut dan apabila air kopi panas tertumpah ke atas tangannya.
State the relationship between the heat capacity and the mass . Nyatakan hubungan diantara muatan haba dengan jisim ( 5 marks) a) Explain why water is normally used as a cooling agent in a car engine. Terangkan mengapa air digunakan bahan penyejuk dalam enjin kereta ( 4 marks) b) An aluminium pan of mass 500 g is heated from 25° C to 105 º C . How much heat is absorbed by the pan ? −1 −1 ( The specific heat capacity of almunium is 910 Jkg °C ) Satu kuali almunium berjisim 500 g dipanaskan daripada 25° C ke 105 º C Berapakah haba yang diserap oleh kuali itu. −1 −1 (Muatan haba tentu aimunium ialah910 Jkg °C ) (4 marks) c) As a researcher, you wish to produce an ideal cooking pan which saves gas for the purpose of cooking. Using the appropriate physic concepts, suggest and explain the modifications required. Sebagai seorang penyelidik anda ingin mencipta suatu kuali , yang boleh menjimatkan gas apabila memasak. Menggunakan konsep fizik yang sesuai ’ cadangkan dan terangkan perubahan –prrubahan yang perlu dilakukan. (6 marks)
10. Diagrams 9.1 and 9.1(b) show interference patterns using coherent sources of waves, λ. Rajah 9.1 dan 9.2 menunjukkan corak-corak interferens gelombang air yang menggunakan sumber gelombang koheren λ
Figure10.1/Rajah 10.1
Figure 10.2/ Rajah 10.2
i) What is meant by coherent waves ? Apakah yang dimaksudkan dengan gelombang koheren? …………………………………………………………………( 1 mark )
ii) Compare Diagrams 10.1 and 10.2 Bandingkan rajah 10.1 dan 10.2 Relate λ and x to make a deduction regarding the relationship of both quantities. ( 5 marks ) Hubungkaitkan antara λ dengan x untuk membuat satu kesimpulan tentang hubungan antara kedua-dua kuantiti itu.
b) Two loudspeakers placed 1.5 m apart are connected to an audio signal generator adjusted to a frequency 600 Hz. When a student walks at a distance of 3.0 m infront of the loudspeakaers he hears four consecutive loud and 3 soft sounds Explain why? ( 4 marks ) Dua pembesar suara di letak pada jarak 1.5 m antara satu sama lain. Keduaduanya disambungkan kepada penjana isyarat audio pada frekuensi 600 Hz Apabila seorang pelajar berjalan pada jarak 3.0 m dihadapan kedua-dua pembesar suara itu, ia mendengar empat bunyi kuat dan tiga bunyi perlahan bertutrutan Terangkan mengapa.. c) i)
Explain why the wavefronts in the sea follow the shape of the coastline as the water becomes shallower. ( 4 marks ). Terangkan mengapa muka gelombang di laut mengikut bentuk pantai bila airnya semakin cetek.
ii)
You plan to build a safe port for the convenience of the fishermen. Suggest relevant steps to be taken in order to build it. Anda bercadang membina sebuah pelabuhan di tepi pantai untuk memudahkan para nelayan belabuh dengan selamat. Cadangkan langkah-langkah yang perlu dilakukan ,agar tempat itu Menjadi pelabuhan yang selamat bagi para nelayan. ( 6 marks)
Bahagian C Section C
[20 markah] [20 marks]
11.
Jawab mana-mana satu soalan daripada bahagian ini. Answer any one question from this question. Diagram 11.1 and Diagram 11.2 show an object of mass 50 kg placed on two identical inclined boards which are pulled by forces of 400N and 271N respectively Rajah 11.1 dan Rajah 11.2 menunjukkan suatu objek berjisim 50 kg diletakkan pada dua buah papan condong yang sama dan ditarik dengan daya 400N dan 271N masingmasing. R
R
400N
271N
100N 35o
100N WA
20o
WA
W W Diagram 11.1 Diagram 11.2 Rajah 11.1 Rajah 11.2 The board in Diagram 11.1 is inclined at 35o to horizontal. The board in Diagram 11.2 is inclined at 20o to the horizontal. The frictional force acting on the object in both situations is 100N each. Papan dalam Rajah 11.1 dicondongkan 35o dari ufuk. Papan dalam rajah 11.2 dicondongkan pada 20o dari ufuk. Daya geseran yang bertindak pada objek pada kedua-dua keadaan itu ialah 100N. (a) State the meaning of frictional force. [1 mark] Nyatakan maksud daya geseran [1 markah] (b) Based on Diagram 11.1 Berdasarkan Rajah 11.1 (i) Calculate the component of weight parallel to the slope of the board, WA. Hitung komponen berat yang selari dengan cerun papan, WA. (ii) Calculate the resultant force acting on the object. Hitung daya paduan yang bertindak pada objek itu. (iii) Determine the direction of movement of the object. Tentukan arah pergerakan bagi objek itu. [5 marks] [5 markah] (c) Use the concept of force, explain why the object in Diagram 11.2 is at rest. Dengan menggunakan konsep daya, terangkan sebab objek berehat di dalam Rajah 11.2 [4 marks]
[4 markah] (d) Diagram 11.3 shows a lawnmower. The handle is inclined at Ө degree to the horizontal. Rajah 11.3 menunjukkan sebuah mesin rumput. Pemegang dicondongkan sudut Ө dari ufuk. Handle Pemegang
Length of handle Panjang pemegang Ө Blade Bilah Diagram 11.3 Rajah 11.3 Table 11 below shows the characteristics of four type of lawnmower, P, Q, R and S. Jadual 11 menunjukkan ciri-ciri bagi 4 jenis mesin rumput, P, Q, R dan S. Lawnmower Angle Ө/o Size of the Length of Mass of the Mesin cutter handle /m lawnmower / kg Sudut Ө/o rumput blade Panjang Jisim bagi mesin Saiz bilah Pemegan rumput / kg pemoton g /m g Big P 80o 5.5 25 Besar Small Q 70o 3.0 100 Kecil Small R 50o 4.5 150 Kecil Big S 30o 1.0 30 Besar Table 11 Jadual 11
Explain the suitability of each characteristics of the lawnmower and determine the most suitable lawnmower to move fast and cut the grass more effectively Terangkan kesesuaian setiap ciri mesin rumput dan tentukan mesin rumput yang paling sesuai untuk memotong rumput dengan lebih berkesan dan bergerak dengan cepat. [10 marks]
[10 markah]
12. a) i) What is meant by effective resistance ? Apakah dimaksudkan dengan rintangan berkesan
( 1 mark )
ii) 6V
I
I
3Ω
1
4Ω I
2Ω
2
A
Figure 11 Three resistors with resistance 2 Ω , 3 Ω , and 4 Ω to a 6V battery as shown in figure 11.
respectively are connected
Tiga perintang 2 Ω , 3 Ω , dan 4 Ω disambungkan kepada bateri 6V seperti rajah11.
If the resistance of the ammeter A can be neglected, what is the effective resistance in the circuit? Jika rintangan ammeter A boleh diabaikan,apakah rintangan berkesan dalam litar.
Find the values of I
1
Tentukan nilai
and
I
1
and I
I 2
2
. ( 4 marks)
b) As a researcher , your duty is to study the characteristics of a material to make a water heater. You are given four choices of metal type T, U,V and W. The table below shows the characteristics of the four metals. Sebagai seorang penyelidik anda ditugaskan untuk mengkaji ciri –ciri bahan yang digunakan untuk membuat pemanas air. Anda diberikan empat jenis logam T,U,V dan W. Jadual di bawah menunjukkan ciri-ciri logam tersebut.
Metal Logam
The cross sectional area Luas keratan rentas
Melting Point Takat lebur
Specific Heat Capacity Muatan haba tentu
Length panjan g
T
Smaller
Low
High
Long
U
Larger
High
Low
Short
V
Smaller
High
Low
Long
W
Larger
High
Low
Short
Table 2/Jadual 2
Based on table 2, Berdasarkan jadual 2, i) Explain the suitable characteristics of the metal to be used to make a heater . Terangkan ciri – ciri logam yang sesuai yang boleh digunakan untuk membuat pemanas air ( 8 marks)
ii) Determine the most suitable metal to be used as the material to make the heater and give your reasons. Tentukan logam yang paling sesuai dan berikan sebab anda ( 2 marks)
END OF QUESTION PAPER
ANSWER 1.
(a) (b) (c)
Kuantiti yang boleh diukur Quantity that can be measured (i) Ralat sifar Zero error (ii) microampere Menolak bacaan dengan ralat bacaan yang ada Subtracting the reading with error reading
1 1 1 1 4
2.
(a)
(i)
Daya graviti Gravitational force (ii) Jatuh bebas Free fal (b) (i) Kesan hentaman dalam rajah (b) lebih besar atau sebaliknya Impact on diagram (b) is greater or vice versa (ii) -Kesan hentaman dalam rajah (a) memanjangkan masa kesan hentaman / atau membengkokkan kaki untuk memanjangkan masa kesan hentaman in diagram (a) lengthen the time of impact / or bending the leg to lengthen time of impact -Mengurangkan daya impuls reduce the impulsive force (c) (i) -Memendekkan tiang / merendahkan buatan shorten the pole / lower the swing -Menghindari kanak-kanak daripada jatuh dari tempat yang tinggi avoid children falling from high place (ii) -pasir / pad pendaratan yang kasar dan lembut sand / rough and soft landing pad -memanjangkan masa kesan hentaman lengthen time of impact -mengurangkan daya impuls reduce impulsive force
1 1 1 2
2
3
10 11
(a) (b)
(i) (ii) (iii)
(c)
(d)
The force which opposes movement Component of weight = mg sin Ө = 50 x 10 x sin 35o = 286.8 N Resultanct force = 400 – 286.8 – 100 = 13.2N The object moves up the inclined plane The forces are in equilibrium Resultant force act on the object is zero The sum of all the horizontal component of the forces is equal to zero The sum of all the vertical components of the force is equal to zero Acceleration is zero when resultant force is zero R = Wy WA+ 100N = 271N Suitable features of lawnmover 1st Low angle of Ө
3rd Big size cutter blade
Reason 2nd Horizontal force will be larger Large resultant force to move the lawnmover forward
9th Lawnmover S is
4th Cut more grass its surface area is larger 6th Easy to handle easy to turn easy to control its movement 8th lighter easy to accelerate 10th any combination of the
choosen
marks 1,2 // 3,4 // 5,6 and 7,8
5th Short length of handle
7th Smaller mass of the lawnmover
1 1 1 1 1 1 4
4 points 4 marks Calculation for resultant force =0 And a = 0 get max 4 marks
10
Examples of 10th mark: Student get mark 10th if student get mark of
1st, 3rd , 5th & 7th b) 2nd, 4th,6th & 8th c) 1st,4th,5th, 7th a)
9. a) The total amount of heat in a body b) 1. the temperature of oil droplet = the temperature of oil poured on the hand 2. the oil droplets have smaller heat capacity 3. the oil poured on the hand has greater heat capacity 4. the heat capacity of droplets transferred to the hand is smaller compared to that of the poured oil 5. The bigger the mass of an object, the bigger the heat capacity of the object c) 1. It doesn’t react to the inner part of the engine 2. high specific heat capacity 3. can absorb large amount of heat energy 4. cheap and easily available d) 1.& 2. : Q = 0.5 x 910 x 80 3 & 4 :. Q= 364 J e) Modification 1.low heat capacity 3. the lid of the pan designed to lower the air pressure inside the pan 5.the lid of the pan made of substance which has weak conductivity of heat
reasons 2. the pan can get hot quickly 4. the boiling point of water decreased 6. heat will not absorbed by the the lid,so heat will not lost to surrounding
10. a) i)The waves that have same frequency and sam phase / sama frekuensi dan sama fasa ii)1. λ diagram 10.1 bigger // λ diagram 10.1 smaller 2. x diagram 10.1 bigger // x diagram 10.2 smaller 3. λ increase , x is increase // λ decrease , x decrease 4. & 5 : x directly proportional to λ b) 1. Sound waves from two loudspeakers produced two coherent sources 2. Sounds wave interfere 3.Constructive interference produced loud sound 4. Destructive interference produced soft sound c)i)1. At the centre of the ocean the water waves travel at uniform speed as the depth
of the sea is uniform 2. When the waves reache the coast ,the water is shallower,wave speed reduced,refraction occurs 3. Refraction causes the wavefront bend toward the normal 4. This results the wavefront following the shape of of coastline
ii) Ubahsuaian 1. dinding konkrit 3. tembok sekatan bercelah 5. tambak laut supaya lebih cetek
Sebab 2. lebih kuat 4. sebarkan tenaga gelombang 6. halaju gelombang berkurang
dan lain-lain yg sesuai.
12 a) i) The total resistace in the circuit / jumlah rintangan dalam litar ii) 1. 1/3 + 1/ 2+4 2. total resistance = 2 ohm 3. I
1
= 2A
4. I
2
= 1A
b) i) Characteristic/ ciri-ciri 1. Smaller surface area 3.High melting point 5. Low specific heat capacity 7. Long (coiled) metal
Reasons/sebab 2. the resistance is higher 4. not easy to melt 6. the temperature arises shortly 8. to increase the resistance
ii) V, because it has,smaller surface area, high melting point, low specific heat capacity and long metal.
(a)(i) (a)(ii)
(b)(i)
(b)(ii) (b)(iii)
(c)
Parallel Selari The other bulb will still light up Mentol yang lain akan terus menyala A bulb that use 12V of potential difference/voltage will release power at 36 J per second/watts Mentol yang menggunakan 12V beza keupayaan / voltan akan melepaskan kuasa 36 J sesaat / watt I = 24/12 = 2.0 A RL = 12/2 =6Ω RH = 12/3 =4Ω 1/ R = 1/6 + ¼ + 1/6 + ¼ = 10/12 R = 1.2 Ω series//Increase the number of bulb in the circuit siri // Menambah bilangan mentol dalam litar
1
1
1
1
1
1
1
1
1 1 1
3
1
1
7 (a) (i) The centre of curvature, C of a curved mirror is the centre of the sphere of the mirror. (ii) - P has a smaller surface curvature. - For concave mirror P, the reflected rays meet at a point further away from the mirror. - For concave mirror Q, the reflected rays meet at a point nearer to the mirror. - Concave mirror P has a large focal length and it has a small surface curvature. - Concave mirror Q has a small focal length and it has a large surface curvature. (b) (i) The image is real, inverted and diminished.
[1 m] [1 m] [1 m] [1 m] [1 m] [1 m] [1 m]
[1 m] (ii The image is virtual, upright and diminished. )
[1 m]
[1 m] (c) (i) - The two lane mirrors are placed at the two ends of a long cardboard box.
[1 m]
- The two mirrors are inclined at 45° to the horizontal as shown in the diagram below.
[1 m]
[2 m] (ii The images are not clear because: ) - Multiple reflections can occur in a mirror and this causes superposition of images. - Mirror will not reflect all the light energy that falls on it. (ii)
[1 m] [1 m]
- To produce clearer images - replace the plane mirrors with two 45° - 45° - [1 m] 90° glass prisms. - There are no multiple reflection in a glass prism and all light energy are [2 m] reflected in total internal reflection. - To produce bigger images - replace a convex lens to act as a magnifier in [1 m] front of the prism at the viewing end.
Q3 Temperature between two bodies is the same because the rate of transfer of heat between the two bodies is the same.
Suhu antara dua jasad adalah sama kerana kadar pengaliran haba antara dua jasad adalah sama.
(ii) 25 °C (b) Heat = mc= 0.25 4 200 (25 –13) = 12 600 J = 12.6 kJ (c) 12 600 = 0.5 c (100 – 25) c = 336 J kg–1 °C–1 (d) No heat is lost to the surrounding. Tiada haba yang hilang ke persekitaran.
