2006 PNEB (PUNTLAND NATIONAL EXAMINATION BOARD)

1. Name .............................................................
School ..................................…………………
Roll Number.........................………………….
Puntland State of Somalia
Ministry of Education
Puntland National Examination Board
Form 4 PHYSICS Examination
June 2006
Time 2 hours
Plus 10 minutes before the exam for reading through the paper
TOTAL TIME 2 hours 10 minutes
INSTRUCTIONS TO CANDIDATES
This paper consists of 12 printed pages.
Count them now. Inform the invigilator if there are any missing.
PART ONE ( 10 Multiple choice questions): 10 marks
PART TWO (Structured questions): 90 marks
TOTAL 100 marks
• Answer ALL questions.
• All answers and working must be written on this paper in the spaces provided
immediately after each question.
• Rough work can be done on page 2. This will not be marked
• No extra paper is allowed.
• No calculators are allowed.

2. Puntland National Examination Board Secondary School Form Four Examination
Puntland Certificate of Education Physics Exam June 2006
• If you make a mistake cross out the incorrect answer clearly and write your
correct answer.
PART ONE Multiple Choice questions
(10 questions, 1 mark each question)
For each question in this section, circle the correct answer, either A or B or C or D
eg.
If you change your mind cross out the answer you have wrongly chosen and clearly
circle the correct answer.
If the examiners think you have marked two answers you will not receive a mark for
that question.
For each question there is only one correct answer.
1. A ray of light strikes a plane mirror through the normal, therefore the angle of
incidence is,
A 300
B 900
C 600
D 1800
2. Said puts two small pieces of metal next to each other with a small gap between
them. Both pieces of metal move away from each other. Then:
A both pieces are magnets
B neither are magnets
C one is a magnet the other is not
D one is a south pole and the other a north pole
3. Mariam has an electric kettle with a power of 3000 Watts connected to a 240v
supply. The cable attached should be able to carry a maximum current of:
A 10.5 amps B 69 amps
C 26amps D 12.5amps
4. Amina wants to cool down her Coca Cola drink, so she puts ice into her drink:
The temperature of the Coca Cola decreases because:
A of the latent heat of vaporisation
B the temperature of the ice goes higher
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A

3. Puntland National Examination Board Secondary School Form Four Examination
Puntland Certificate of Education Physics Exam June 2006
C the heat energy is taken from the water
D the ice gives out heat
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4. Puntland National Examination Board Secondary School Form Four Examination
Puntland Certificate of Education Physics Exam June 2006
5. In the upper atmosphere the temperature drops and invisible water vapour forms
water droplets called clouds. This is an example of:
A evaporation B condensation
C fusion D freezing
6. Xaji doesn’t know which instrument to use to show electric charge.
He should use:
A a voltmeter B an ammeter
C a multimeter D an electroscope.
7. 1cm3
is the same as:
A. 10 mm3
B 1 millilitres3
C 1 x 10-3
mm3
D 1 x 10-3
litres
8. Fadumo rings a bell once loudly, the bell is 330m away from a big wall, so the Echo
of the bell will reach her in:
A 2 seconds B 1 second
C 4 seconds D 0.5 seconds
9. Hawa wants to find the exact volume of an irregular shaped stone. So she should:
A. weigh it and divide the density by the mass
B. measure it with a ruler and multiply length x breadth x height.
C. place it in a large measuring cylinder with water in it and see how much the
water rises.
D. cover it completely with paper and measure the surface area of the paper.
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5. Puntland National Examination Board Secondary School Form Four Examination
Puntland Certificate of Education Physics Exam June 2006
10.Shukri walks into a dark room looking for her bag. She switches on the lamp.
Please circle the correct drawing, either A, B, C,or D, which shows the correct
light rays to explain why she can now see her bag:
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6. Puntland National Examination Board Secondary School Form Four Examination
Puntland Certificate of Education Physics Exam June 2006
PART TWO Structured Questions
Total 90 Marks ANSWER ALL QUESTIONS (2) marks means 2 marks.
Question 11. The graph represents the velocity –time graph of a Mark 2 Toyota.
↑velocity m/s
B
4
A
2
C
D
0 4 8 12 16 20 Time (seconds)
Choose the correct words and figures to complete the sentences chosen from:
Displacement, velocity, acceleration, distance, speed, retardation,
2m/s, 4m/s, 0m/s, 1m/s2
, 2 m/s2
, 20s, 4s, 12s, 16s,20s,scalar,vector
a) The part of graph A represents an ……………………….…….of 1m/s2
(1)
b) The part of graph B represents a velocity of ………………… (1)
c) The ……………………………..for the whole journey is 64m. (1)
d) The part of graph C represents a ………..…………………..of …... (2)
e) The time taken when the Mark 2 is travelling at a constant speed is
……….sec (1)
f) The part of graph D represents … ……… (1)
g) velocity is a ……………… and speed is a …………………… (2)
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7. Puntland National Examination Board Secondary School Form Four Examination
Puntland Certificate of Education Physics Exam June 2006
Question 12.
air sand water Three beakers A, B, and C are shown.
HE is the heat energy needed to raise the
temperature of the water and the sand by
10
C
A B C
Mass 250g 500g 500g
HE 200j 1050j
a) What is the mass of the sand or water in kg? ..........................kg (2)
b) Calculate, in joules/kg for 10
C rise, the specific heat capacity of
i) sand (4)
(ii) water. (2)
c) Why does the desert sand, next to a lake, heat up quicker than the water in the lake?
………………………………………………………………………………………………………………….
…………………………………………………………………………………………………………………
……………………………………………………………………………………………………(2)
Question 13. Ali boils a large container of hot water and Yusuf lights a match.
Using the words, lower and higher complete the sentences to show the difference
between heat and temperature:
The hot water in the container has ……………… heat energy,
but ………………..…temperature than the match. (2)
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8. Puntland National Examination Board Secondary School Form Four Examination
Puntland Certificate of Education Physics Exam June 2006
Question 14. The circuit below represents a transformer and a resistance R
.
240v AC ~
1 amp
1000turns 100 turns
Fill in the spaces
I. Is it a ‘step down’ or ‘step up’ transformer? ………………………………………(1)
II. Calculate the current flowing through R ……………………………………………(1)
III. Calculate the (p.d) voltage flowing through R ………………………………………
…………..…… volts (1)
IV. Find the resistance of R
…………ohms (2)
V. Give 2 examples where transformers are used
……………………………………………………………………………………..
……………………………………………………………………………………………. (2)
Question 15. Look at the graph of a wave below:
0 1 2 3 seconds
B
a) What is the name of B …………………………………………………….. (1)
b) How many wavelengths are shown here? ……… (1)
c) What is the period? ………………………………………………………….. ….(1)
d) What is the frequency of the wave in Hz………………………………………..
……………………………………………………………………………………………
…………………………………………………………………………………………..(2)
e) What would be the speed of this wave if its wavelength is 2m? (2)
)
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R

9. Puntland National Examination Board Secondary School Form Four Examination
Puntland Certificate of Education Physics Exam June 2006
Question 15 contd
Complete:
f) Light is a …………………….. wave and sound is a ………………………….wave
(2)
g) Use some of the words higher, lower, longer, shorter to complete the sentences,
Ultra violet waves have a ………………..frequency and a ………………..wavelength
than light waves and Infra red waves have a …………………..frequency and a
………………..wavelength than light waves. (2)
Question 16. Estimate and write down the values shown by the arrows on the
scales:
a)
0.01 0.02 Ans…….. (1)
b)
1.0 1.5 2.0 2.5 Ans…………(1)
c)
0 1000 Ans……….. (1)
d)
100
200 Ans……………(1)
e) 1
5 Ans……………(1)
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10. Puntland National Examination Board Secondary School Form Four Examination
Puntland Certificate of Education Physics Exam June 2006
Question 17. A stone (or pendulum bob) swings back and forth from a retort stand as
shown below.
Q S
P
stone
R
a) P is the ………………………….. of the oscillation
b) The maximum kinetic energy is at ……………..
c) The maximum potential energy is at ………………….. (3)
17.d) contd. When you start counting the swings, do you count from zero or one?
Ans……......(1)
e) We want to count one oscillation only, do we count one oscillation
i) from Q to S or ii) from Q to S and back to Q Ans… (1)
g) If you wanted the accurate time of ONE oscillation of the stone, what is the
minimum number of oscillations you need to time with a stopwatch.
Ans …… swings (1)
h) Abdullahi says that if you put a heavier stone, the time of the oscillation changes,
True or False? Ans……….. (1)
Question 18. The following is a graph of the change of state of a solid to a gas
temperature 0
C
.
400 D
C
200 B
120 A
0 5 10 15 20 (seconds) Time
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11. Puntland National Examination Board Secondary School Form Four Examination
Puntland Certificate of Education Physics Exam June 2006
Question 18.contd. Write down exactly what each line of the graph represents in the
change of state and write down the temperature at each stage :
a) line A…………………………………………………………………………………….(1)
temp………………………………..(1)
b) line B…………………………………………………………………………………….(1)
temp………………………………..(1)
c) line C…………………………………………………………………………………….(1)
temp………………………………..(1)
d) line D…………………………………………………………………………………….(1)
temp………………………………..(1)
Question 19.
What value of Z should be placed at F to keep the equilibrium of the beam?
(Use the principle of moments)
D 4y E y F
Z
?
Ans………………….. (3)
Question 20. Draw only 2 rays of light through the lens and use them to draw the
image of the object (3)
C F F C
object
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12. Puntland National Examination Board Secondary School Form Four Examination
Puntland Certificate of Education Physics Exam June 2006
Question 21.
R is the emerging light ray, after a ray of incident light has passed through the prism.
Draw accurately the original incident ray and the refracted ray thru the prism (2)
R
r0
Normal
Glass block
Question 22. Dayib pushes a bar magnet quickly in the direction of the arrow in and out
of a coil of wire which is connected only to a galvanometer. The coil actually has 50 turns.
P Q
Galvonometer
Complete the sentences:
(a) The induced magnetic field from the magnet will cause the end of the coil P to
become a:…………….. Pole (1)
(b) What will happen to the pointer on the galvanometer when the magnet:
(i) moves in and out of the coil?.......................................................................
……………………………………………………………………………………………………..(1)
(ii) remains stationary inside the coil? .………………..
…………………………………………………………………………… ……..(1)
(c) The current produced is ……………………………current (1)
(d) To generate more electricity we need to:
a) …………………………………… b) ………………………………… ………………. .(2)
Question 23. Nimo dives in the sea at Bosaso to a depth of 50m. Calculate the water
pressure on her at this depth. [g = 10N/kg, density of sea water =1200kg/m3
] (3)
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S

13. Puntland National Examination Board Secondary School Form Four Examination
Puntland Certificate of Education Physics Exam June 2006
Question 24. Complete the sentences
a) The energy difference between one point and another in a flow of electrons is
called
…………………………………………………………………………………………..(2)
b) A stone is attached to a rope and moves in a circle, the acceleration is towards
the………………….. (2)
c) …………………………………….occurs when someone passes by and even at a
distance you can smell his/her perfume.
d) The acceleration of a car from rest to 20m/s in 2 seconds is…………………2)
and if the mass of the car is 1 tonne(1000kg) then its accelerating force is
…………
……………………………………………………………………………………………..(2)
and its change in momentum is ...........
…………………………………………………………………………………………(2)
e) Two lamps of 3 ohms and 2 ohms are in parallel in a circuit with a 12v battery what
is the current flowing round the whole circuit
.....................................................................................................................................
.....................................................................................................................................
………………………………………………………………………………………………….(2)
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