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Physics – Form 5 Secondary – Track 3 – 2015 Page 1 of 12
DIRECTORATE FOR QUALITY AND STANDARDS IN EDUCATION
Department of Curriculum Management
Educational Assessment Unit
Annual Examinations for Secondary Schools 2015
FORM 5 PHYSICS Time: 2 hours
Name: ______________________________ Class: _______________
Answer ALL questions in the spaces provided on the Examination Paper.
All working must be shown. The use of a calculator is allowed.
Where necessary take the acceleration due to gravity 𝐠 = 𝟏𝟎 𝐦/𝐬𝟐.
Marks Grid: For the Examiners’ use ONLY
Question 1 2 3 4 5 6 7 8 9 10 11 12 Th. Prac Total Final Mark
Mark 10 10 10 10 10 10 10 20 20 20 20 20 170 30 200 100
Score
Density m = ρ V
Pressure P = ρ g h F = P A
Moments Moment = F × perpendicular distance
Energy PE = m g h KE =
1
2mv2 Work Done = F s
Work Done = Energy Converted E = P t
Force F = m a W = m g
Motion Average Speed =
total distance
total time s =
(u + v) t
2 s = ut +
1
2at2
v = u + at v2 = u2 + 2as Momentum = m v
Electricity
Q = I t V = I R E = Q V
P = I V R ∝ 𝐿/𝐴 E = I V t
RT = R1 + R2 + R3 1
RT=
1
R1+
1
R2
Electromagnetism N1
N2=
V1
V2
Heat ΔQ = m c Δθ
Waves
η =real depth
apparent depth η =
speed of light in air
speed of light in medium
f =1
T
v = f λ m =
hi
ho=
image distance
object distance
Radioactivity A = Z + N
Track 3
Page 2 of 12 Physics – Form 5 Secondary – Track 3 – 2015
solar energy
cold water in
hot water out
storage tank
solar
collector
Figure 1
Section A: This section has 7 questions. Each question carries 10 marks (70 marks).
1. A solar water heater is shown in Figure 1.
a) The solar collector is dark coloured. Why?
___________________________________________ [1]
b) Why is the back of the solar collector well insulated?
___________________________________________ [2]
c) Why is the storage tank placed above and not below
the solar collector?
_______________________________________________________________________________ [2]
d) A student is told that heat from the sun reaches the solar collector by convection. Is this statement
correct? Explain.
_______________________________________________________________________________ [2]
e) Why are the pipes used in the solar water heater made of a metal such as copper?
_______________________________________________________________________________ [1]
f) The pipes are also long and in the shape of a coil. Why?
_______________________________________________________________________________ [2]
2. Maria places two iron cores in a cardboard tube as shown in Figure 2. When she closes the switch she
observes that the iron cores move.
Figure 2
a) Draw arrows to represent the direction of the current through the coil. [1]
b) End X becomes a ____________ pole while end Y becomes a ____________ pole. [2]
c) In which direction do the iron cores move? Explain.
_______________________________________________________________________________ [2]
d) Draw an arrow on each plotting compass to indicate the direction of the magnetic field. [2]
e) State one way by which the magnetic field can be made stronger.
_______________________________________________________________________________ [1]
f) The polarity of the battery is reversed. Explain why the movement of the iron cores is unchanged.
_______________________________________________________________________________ [2]
Figure 2
iron cores plotting
compass
coil
switch battery
X Y
cardboard tube
Physics – Form 5 Secondary – Track 3 – 2015 Page 3 of 12
3. The Andromeda galaxy is 2.5 million light years away from Earth.
a) Name the instrument used to observe such a distant galaxy.
______________________________________________________________[1]
b) What is a galaxy made up of?
_______________________________________________________________________________ [1]
c) Define the term light year.
_______________________________________________________________________________ [2]
d) Change 1 light year to metres. The speed of light is 3×108 m/s.
__________________________________________________________________________________
_______________________________________________________________________________ [3]
e) Name one benefit of space exploration.
_______________________________________________________________________________ [1]
f) Name one question about the Universe that is still unanswered to this day.
_______________________________________________________________________________ [2]
4. Tony is driving his car at a speed of
20 m/s. He sees a dog sitting in the
middle of the road 75 m ahead. The car moves a distance of 12 m before he starts to apply the brakes.
He eventually manages to stop the car 6 seconds after braking.
a) Calculate his reaction (thinking) time.
_______________________________________________________________________________ [1]
b) Calculate his braking distance.
_______________________________________________________________________________ [2]
c) Work out the total stopping distance.
_______________________________________________________________________________ [1]
d) Using the answer in part ‘c’, state whether he will hit the dog.___________________________ [1]
e) Find the deceleration of the car.
_______________________________________________________________________________ [2]
f) Given that the mass of the car is 1500 kg, determine the braking force needed to stop the car.
__________________________________________________________________________________
_______________________________________________________________________________ [2]
g) Tony accelerates to 30 m/s. His reaction time (increases, decreases, remains the same). [1]
Figure 3
sees dog starts braking
Figure 4
dog
Page 4 of 12 Physics – Form 5 Secondary – Track 3 – 2015
piston A piston B
oil tank
lever
valve 1
tap (closed)
valve 2
5. a) Daniela and Thomas are carrying out an experiment on electrostatics.
i) Daniela argues that a neutral perspex (acetate) strip has no charges at all. Do you agree?
Explain.
_______________________________________________________________________________
____________________________________________________________________________ [2]
ii) When Daniela rubs the perspex strip with a cloth, it acquires a positive charge because
______________ are transferred from the ______________ to the ____________________ [3]
b) Lightning occurs when there is a very large amount of static electricity in clouds.
During a lightning strike the average current flowing is 45 000 A. The amount of
electric charge delivered during the strike is 5 C.
i) Calculate the duration of a lighting strike.
____________________________________________________________________________ [2]
ii) Given that the energy dissipated is 6 × 108 J (600 000 000 J), calculate the voltage present.
_______________________________________________________________________________
____________________________________________________________________________ [3]
6. In the hydraulic jack shown in Figure 6, the lever
is pushed down several times making the van
rise by a certain height each time. The valves
allow the oil to flow in one direction.
a) State the advantage of using a hydraulic
system.
_______________________________________________________________________________ [1]
b) Why are liquids used in hydraulic systems?
_______________________________________________________________________________ [2]
c) Which valve prevents the van from going down after it is lifted?
_______________________________________________________________________________ [1]
d) Predict what happens when the tap is opened.
_______________________________________________________________________________ [2]
e) The area of piston A is 0.0004 m2 while that of piston B is 8 m2. If the van’s mass is 2200 kg,
calculate:
i) the pressure exerted by the van on the liquid.
____________________________________________________________________________ [2]
ii) the force applied by the lever on piston A.
____________________________________________________________________________ [2]
Figure 6
Figure 5
Physics – Form 5 Secondary – Track 3 – 2015 Page 5 of 12
7. Noel carried out an experiment on moments using a metre ruler.
a) State the two conditions needed for a system to be in equilibrium.
__________________________________________________________________________________
_______________________________________________________________________________ [2]
b) The metre ruler he sets up is shown in Figure 7. It is pivoted at its midpoint but is not balanced.
Figure 7
i) Show (through calculation) that the resultant moment is 0.3 N m.
_______________________________________________________________________________
_______________________________________________________________________________
____________________________________________________________________________ [3]
ii) State the direction in which the metre ruler turns.__________________________________ [1]
c) A builder needs to move a concrete brick using a wheelbarrow. Figure 8 shows two different
wheelbarrows having the same brick placed in a different position.
i) Explain why the concrete block in wheelbarrow B is not producing a turning effect.
____________________________________________________________________________ [1]
ii) Explain, by making use of the terms moment, force and perpendicular distance, the advantage
of having longer handles as in wheelbarrow B.
_______________________________________________________________________________
_______________________________________________________________________________
____________________________________________________________________________ [3]
2N 2N 1N
0.5 m 0.1 m 0.4 m
wheelbarrow A wheelbarrow B
Figure 8
Page 6 of 12 Physics – Form 5 Secondary – Track 3 – 2015
Section B. This section has 5 questions. Each question carries 20 marks (100 marks).
8. This question is about motion.
a) Daria and Max are supplied with an air track, a glider, a light gate and a data logger as shown in
Figure 9. The data logger measures the velocity of the glider as it passes through the light gate.
Figure 9
i) Name an additional apparatus that the students need to calculate the kinetic energy of the
glider.
____________________________________________________________________________ [1]
ii) Their teacher asks them to investigate how the kinetic energy of the glider depends on its
velocity. Describe the method they should use, including how they can present their results.
_______________________________________________________________________________
_______________________________________________________________________________
_______________________________________________________________________________
____________________________________________________________________________ [4]
iii) Daria and Max predict that the kinetic energy increases with increasing velocity. Do you agree
with this prediction? __________ [1]
b) A toy truck of mass 1.25 kg moving at 3 m/s collides with a stationary ball of mass 0.25 kg. After
the collision, the toy truck moves at 2 m/s, while the ball moves with a different velocity.
i) Calculate the total momentum before collision.
____________________________________________________________________________ [3]
ii) What is the total momentum after collision? Explain.
____________________________________________________________________________ [2]
iii) Calculate the velocity of the ball after the collision.
_______________________________________________________________________________
_______________________________________________________________________________
____________________________________________________________________________ [3]
iv) Show that the total kinetic energy before collision is 5.625 J.
____________________________________________________________________________ [3]
data logger
air track
glider
light gate
Physics – Form 5 Secondary – Track 3 – 2015 Page 7 of 12
v) Show that the total kinetic energy after the collision is equal to the total kinetic energy before
collision.
_______________________________________________________________________________
____________________________________________________________________________ [3]
9. This question is about electricity.
a) Bradley and Diana are required to find the electrical energy, E, consumed in 5 minutes by a DVD
player. They take readings off the joulemeter every minute as shown in the table of results below.
Electrical energy consumed E / J 0 1500 3000 4500 5000 7500
time t / minutes 0 1 2 3 4 5
i) Plot a graph of electrical energy E in joules consumed by the DVD player (y-axis) against the
time t in minutes (x-axis) on the graph paper provided. [5]
ii) Bradley reads incorrectly the quantity of electrical energy E consumed by the DVD after
4 minutes. Use your graph to determine the correct value of E after 4 minutes.
____________________________________________________________________________ [1]
iii) Is electrical energy E consumed by the DVD directly proportional to time? Explain your
answer.
_______________________________________________________________________________
____________________________________________________________________________ [3]
iv) Calculate the time in seconds during which the DVD is turned on.
____________________________________________________________________________ [1]
v) From your graph or otherwise calculate the power of the DVD.
_______________________________________________________________________________
____________________________________________________________________________ [2]
vi) Diana watches a 150-minute film on the DVD player. Calculate the number of kWh consumed
during this time.
_______________________________________________________________________________
_______________________________________________________________________________
_______________________________________________________________________________
____________________________________________________________________________ [3]
Page 8 of 12 Physics – Form 5 Secondary – Track 3 – 2015
b) The diagram shows a power ring circuit
and an incompletely connected 13-A
socket.
i) From the diagram, what indicates
that wire P is the live wire?
_________________________ [1]
ii) State the colour of the insulation of
the:
1. Neutral
wire:____________________________________________________________ [1]
2. Earth wire:_____________________________________________________________ [1]
iii) Draw the two missing socket connections to the ring circuit. [2]
10. This question is about radioactivity and half-life.
a) Figure 11 shows two instruments used in
measuring the activity of radioactive
substances.
i) Name instrument Q.
______________________________ [1]
ii) Name instrument R.
______________________________ [1]
iii) Which of the above instruments is used to detect radiation emitted by unstable nuclei?
____________________________________________________________________________ [1]
iv) Which of the above instruments gives the number of unstable nuclei decaying (breaking down)
over a period of time?
____________________________________________________________________________ [1]
b) Gregg finds out that the rate of decay of a newly discovered radioactive isotope X is
1025 counts/minute. He notices that when the radioactive isotope X is not present, the reading
drops to 25 counts/minute.
i) Explain why the count rate does not fall to zero when the radioactive isotope X is not present.
____________________________________________________________________________ [1]
ii) Name two sources of this radiation.
_______________________________________________________________________________
____________________________________________________________________________ [2]
CounteRadioactive
source Q
R
from mains supply
30-A fuse
13-A socket P Q R
Figure 10
Figure 11
Physics – Form 5 Secondary – Track 3 – 2015 Page 9 of 12
c) While investigating the half-life of radioactive isotope X, Gregg records the data in the table
below.
Time / (hours) 0 0.5 1.0 1.5 2.0 2.5
Total count rate / (counts/min.) 1025 863 622 523 447
Background count rate / (counts/min.) 23 25 22 23 27
Corrected count rate / (counts/min.) 1000 840 710 600 420
i) Complete the following statement about half-life:
Half-life is the time taken for __________ the nuclei of a sample of a radioactive substance to
decay. [1]
ii) Complete the missing values in the above table. [3]
iii) Use the table to calculate the half-life of the radioactive isotope X.
_______________________________________________________________________________
____________________________________________________________________________ [2]
d) Calculate the mass of radioactive isotope X which remains after 6 h given that the initial mass of
this isotope was 8 g.
__________________________________________________________________________________
_______________________________________________________________________________ [3]
e) Name:
i) two main uses of radioactive isotopes.
_______________________________________________________________________________
____________________________________________________________________________ [2]
ii) two main safety measures when dealing with radioactive substances.
_______________________________________________________________________________
____________________________________________________________________________ [2]
Page 10 of 12 Physics – Form 5 Secondary – Track 3 – 2015
11. This question is about the motor effect of an electric current.
a) Robert sets a loosely held vertical wire PQ between the poles of a powerful magnet and closes the
switch S. He observes that the wire PQ moves.
Figure 12
i) Underline: The wire section PQ moves (inwards, outwards, left, right). [1]
ii) Name the force causing the wire PQ to move.____________________________________ [1]
iii) Name the rule which helps Robert determine the direction of movement of wire section PQ.
____________________________________________________________________________ [1]
iv) Name two ways through which the force acting on wire section PQ can be decreased.
____________________________________________________________________________ [2]
v) State two ways in which this force can be made to act in the opposite direction.
____________________________________________________________________________ [2]
vi) Why is the rheostat R included in the circuit?
____________________________________________________________________________ [2]
vii) State what change, if any, is observed when the battery is removed and replaced by a low
frequency a.c. supply.
_______________________________________________________________________________
____________________________________________________________________________ [2]
b) Figure 13 below represents a d.c. motor.
Figure 13
N S
P
Q
A
S
R
I
N S
B C
D A
− +
Physics – Form 5 Secondary – Track 3 – 2015 Page 11 of 12
i) Coil section _____ experiences a force pushing it out of the plane of the paper when the
electric current flows through the coil. [2]
ii) Which section of the coil does NOT experience a force?____________________________ [2]
iii) Give a reason why the section of coil referred to in question (ii) does not experience a force.
_______________________________________________________________________________
____________________________________________________________________________ [2]
iv) State the direction of rotation of the motor shown in Figure 13. ______________________ [2]
v) Name an appliance which makes use of an electric motor.
____________________________________________________________________________ [1]
12. This question is about measuring the specific heat capacity of sea water.
a) Nadia and Joanne are required to find the specific heat capacity of a sample of sea water collected
from Golden Bay. They are supplied with the following apparatus:
beaker containing some sea water; d.c. immersion heater; d.c. power supply; joulemeter;
lagging material; lid; electronic balance; thermometer and a stirrer.
Describe how Nadia and Joanne should carry out their investigation. Your answer should include:
i) a labelled diagram of the experimental setup.
[3]
ii) the three measurements required to find the specific heat capacity of sea water apart from the
room temperature.
_______________________________________________________________________________
____________________________________________________________________________ [3]
iii) the three items of apparatus required to collect these measurements.
_______________________________________________________________________________
____________________________________________________________________________ [3]
Page 12 of 12 Physics – Form 5 Secondary – Track 3 – 2015
iv) Name two precautions which must be taken during this investigation.
_______________________________________________________________________________
_______________________________________________________________________________
____________________________________________________________________________ [2]
b) Nadia plots a graph of the change in temperature Δθ of sea water against heat energy supplied Q
as shown below.
Use Nadia’s graph to:
i) calculate the change in temperature of the mass of sea water when the quantity of heat supplied
to the sea water is 5000 J.
____________________________________________________________________________ [1]
ii) predict the quantity of heat required to raise the temperature by 6 °C. __________________ [2]
iii) find the specific heat capacity of sea water given that its mass is 0.5 kg.
_______________________________________________________________________________
_______________________________________________________________________________
____________________________________________________________________________ [3]
iv) determine the room temperature, given that the final temperature reached by sea water when
10000 J of heat energy are supplied is 20 °C.
_______________________________________________________________________________
____________________________________________________________________________ [2]
c) What do you notice from Nadia’s graph that shows that the beaker containing the sea water is very
well-lagged?
____________________________________________________________________________ [1]
0
1
2
3
4
5
6
0 2000 4000 6000 8000 10000 12000
/
C
Q / J
Graph of temperature change against heat energy supplied Q