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Physics – Form 5 Secondary – Track 2 – 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 2
Page 2 of 12 Physics – Form 5 Secondary – Track 2 – 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 2 – 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 car stops starts braking
Figure 4
dog
Page 4 of 12 Physics – Form 5 Secondary – Track 2 – 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 2 – 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 2 – 2015
Section B. This section has 5 questions. Each question carries 20 marks (100 marks).
8. This question is about motion.
a) Complete the following:
Speed is a ___________________ quantity. Vector quantities, such as velocity, have both
______________ and ________________. [3]
b) Daria and Max have 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) Why is an air track used in experiments involving moving objects?
____________________________________________________________________________ [2]
ii) Write the equation that relates kinetic energy to velocity. ___________________________ [1]
iii) Which other physical quantity is needed to calculate the kinetic energy of the glider?
___________________________________________________________________________ [1]
Their teacher asks them to investigate how the kinetic energy of the glider depends on its velocity.
iv) How can they make the gliders move at different velocities?
____________________________________________________________________________ [1]
v) Add the missing units to the quantities in the table below.
Quantity Unit
Velocity
Kinetic energy
[2]
vi) Daria and Max predict that kinetic energy increases with increasing velocity. Do you agree
with this prediction? __________ [1]
c) A toy truck of mass 1.2 kg moving at 3 m/s to the right hits a stationary ball of mass 0.4 kg. After
the collision, the toy truck keeps going at 2 m/s while the ball moves with a different velocity.
Figure 10
data logger
air track
glider
light gate
Before
0 m/s 3 m/s 2 m/s v
After
Physics – Form 5 Secondary – Track 2 – 2015 Page 7 of 12
i) Calculate the total momentum before collision.
____________________________________________________________________________ [2]
ii) State the total momentum after collision. ________________________________________ [1]
iii) Find the momentum of the toy truck after the collision.
____________________________________________________________________________ [2]
iv) Hence, find the momentum of the ball after the collision
____________________________________________________________________________ [2]
v) Calculate the velocity of the ball after the collision.
____________________________________________________________________________ [2]
9. This question is about electricity.
a) Bradley and Diana want to find how much electrical energy, E, a DVD player uses. They use a
joulemeter to measure the electrical energy used every minute, as shown in the table below.
time t / (minutes) 0 1 2 3 4 5
Electrical energy used E / (J) 0 1500 3000 4500 6000 7500
i) Plot a graph of electrical energy E in joules J (y-axis) against time t in minutes (x-axis) on the
graph paper provided. [5]
ii) From your graph, how can you tell that electrical energy E is directly proportional to time t?
____________________________________________________________________________ [2]
iii) Calculate the time in seconds during which the DVD player is switched on.
____________________________________________________________________________ [1]
iv) Calculate the power of the DVD player.
_______________________________________________________________________________
____________________________________________________________________________ [3]
v) Complete: Energy can neither be ________________ nor ________________ but it can be
________________ from one form to another. [3]
b) The diagram in Figure 11 shows a power ring
circuit and an incompletely connected 13 A
socket.
i) Which wire (P, Q or R) is the live wire?
How do you know this?
__________________________________ [2]
ii) What colour/s is the earth wire?
__________________________________ [2]
iii) Add to the diagram two wires that connect
the ring circuit correctly to the socket. [2]
from mains supply
P Q R
30 A fuse
13 A socket
Figure 11
Page 8 of 12 Physics – Form 5 Secondary – Track 2 – 2015
10. This question is about radioactivity and half-life.
a) Figure 12 shows two instruments used in measuring the activity of radioactive substances.
i) Name instrument Q.
________________________________[1]
ii) Name instrument R.
________________________________[1]
iii) Which one (Q or R) is used to detect
radiation emitted by unstable nuclei?
______________ [1]
iv) Which one (Q or R) gives the number of unstable nuclei decaying (breaking down) over a
period of time? ______________ [1]
b) Gregg found that the rate of decay of a 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) Why is there still a count rate when the radioactive isotope X is removed?
____________________________________________________________________________ [1]
ii) Name two sources of this radiation.
_______________________________________________________________________________
____________________________________________________________________________ [2]
c) Gregg starts filling the table below while investigating the half-life of radioactive isotope X.
Gregg knows that the corrected count rate = total count rate – 25 counts/minute .
Time / (hours) 0 0.5 1.0 1.5 2.0 2.5
Total count rate / (counts/min.) 1025 865 625 525 445
Corrected count rate / (counts/min.) 1000 840 710 600 420
i) Complete the missing values in the above table. [2]
ii) Complete the following statement about half-life:
Half-life is the time taken for __________ the nuclei of a sample of a radioactive substance to
__________. [2]
iii) Use the table to calculate the half-life of the radioactive isotope X.
_______________________________________________________________________________
____________________________________________________________________________ [2]
iv) Calculate the mass of radioactive isotope X which remains after 3 half-lives given that the
initial mass of this isotope was 8 g.
8 g → ________ →_________ →_________
[3]
CounteRadioactive
source Q
R
Figure 12
Physics – Form 5 Secondary – Track 2 – 2015 Page 9 of 12
d) Name:
i) two main uses of radioactive isotopes.
_______________________________________________________________________________
____________________________________________________________________________ [2]
ii) two main safety precautions when dealing with radioactive substances.
_______________________________________________________________________________
____________________________________________________________________________ [2]
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 13
i) Underline: The wire section PQ moves (inwards, outwards, left, right). [1]
ii) On the diagram add an arrow to show the direction of the magnetic field. [1]
iii) Name the force causing the wire PQ to move._____________________________________ [1]
iv) Name the rule which helps Robert determine the direction of movement of wire section PQ.
____________________________________________________________________________ [1]
v) Underline the correct answer:
What happens to the force on wire PQ if:
1. the magnet is replaced by a stronger one? (increases / decreases / stays the same) [1]
2. a stronger current flows through PQ? (increases / decreases / stays the same) [1]
vi) State two ways in which this force can be made to act in the opposite direction.
____________________________________________________________________________ [2]
vii) Give the names of the circuit components A, R and S in the circuit.
____________________________________________________________________________ [3]
N S
P
Q
A
S
R
I
Page 10 of 12 Physics – Form 5 Secondary – Track 2 – 2015
b) Figure 14 below represents a d.c. motor.
Figure 14
i) Draw the direction of the current in coil sections AB and CD. [2]
ii) Coil section _____ experiences a force pushing it out of the page when the electric current
flows through the coil. [2]
iii) Which section of the coil does NOT experience a force? Give a reason for your answer.
_______________________________________________________________________________
____________________________________________________________________________ [3]
iv) Underline one of the statements below that best describes the motion of coil ABCD:
1. It will move out of the paper.
2. It will move into the paper.
3. It will rotate. [1]
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.
Nadia and Joanne want to find the specific heat capacity of some sea water taken from Golden Bay.
They have the following apparatus:
a) Complete the diagram of the apparatus used in the experiment by adding the missing apparatus
and labels. [4]
beaker containing some sea water; d.c. heater; d.c. power supply; electronic balance;
joulemeter; thermometer; lagging material; lid; stirrer,
N S
B C
D A
− +
Physics – Form 5 Secondary – Track 2 – 2015 Page 11 of 12
b) Name the instrument they need to find the mass of the sea water.
_______________________________________________________________________________ [1]
c) Explain what they need to do to find the mass of the sea water.
__________________________________________________________________________________
__________________________________________________________________________________
_______________________________________________________________________________ [3]
d) Name the instrument they need to find the temperature of the sea water.
_______________________________________________________________________________ [1]
e) What is the use of the stirrer?
__________________________________________________________________________________
_______________________________________________________________________________ [1]
f) The initial temperature of the sea water is 20 °C and the final temperature is 35 °C. Calculate the
change in temperature.
_______________________________________________________________________________ [1]
g) What is assumed during the experiment regarding heat losses?
_______________________________________________________________________________ [1]
h) Give any two precautions related to this experiment.
__________________________________________________________________________________
_______________________________________________________________________________ [2]
i) The mass of sea water is 0.30 kg and the joulemeter reading is 18000 J. Calculate the specific heat
capacity of sea water.
__________________________________________________________________________________
_______________________________________________________________________________ [3]
j) Nadia reads in a physics book that the specific heat capacity of pure water is 4200 J/kg °C.
i) Salt (increases / decreases) the specific heat capacity of pure water. [1]
ii) Which boils more quickly from the same temperature, 1 kg of pure water or 1 kg of salt water?
____________________________________________________________________________ [2]
Page 12 of 12 Physics – Form 5 Secondary – Track 2 – 2015
