NATURAL SCIENCES
CONTROL TEST
GRADE 8
MARCH 2018
EXAMINER: A. Oelofse
TOTAL: 35
MODERATOR: S. du Plessis TIME: 1 hour
INSTRUCTIONS:
1. This test consists of five questions.
2. Answer all the questions.
3. Number each question exactly as the test.
4. Carefully read through the test before you answer.
Gr. 8 ~ Natural Sciences
March 2018
QUESTION 1
Multiple-choice questions
Four possible answers are given for the following questions. Choose the correct answer and
write the letter next to the question number, i.e. 1.1 D.
1.1
The diagram below represents a food web. Each letter represents a species and the arrows
indicate the flow of energy.
E
F
C
D
A
B
Which one of the following shows the species correctly according to the role of each in the food
web?
A.
Predator
A
Producer
F
Decomposer
F
Primary consumer
B
B.
E
A
F
D
C.
C
F
A
E
D.
E
A
F
C
1.2
Which one of the following does not form part of the carnivore group?
A.
Predators B.
Detritivores
C.
Scavengers
D.
Insectivores
1.3
Which element is used to test for the presence of starch?
A.
Iodine
B.
Bromine
C.
Chlorine
D.
Carbon
1.4
Which option in the chart below correctly pairs a human activity with its impact on the
environment?
Human activity
A. Decrease in the use of pesticides
Impact
Erosion of rock in the soil
B. Increase in housing developments
Improvement in air quality
C. Decrease in recycling
Reduction in amount of available resources
D. Increase in human population
Reduction in water usage
2
Gr. 8 ~ Natural Sciences
1.5
March 2018
The setup below shows four test tubes. Tube 1 contains water only. Tube 2 contains a live snail.
Tube 3 contains a live green water plant. Tube 4 contains both a live green water plant and a
live snail.
Tube 1
Tube 2
Tube 3
Tube 4
In this setup, which tubes contain at least one organism performing cellular respiration?
A.
Tubes 1 and 2 only
B.
Tubes 2 and 4 only
C.
Tubes 3 and 4 only
D.
Tubes 2, 3, and 4 only
(1)
(5 × 1) = [5]
QUESTION 2
One-word items:
Give one word/term for each of the following descriptions.
2.1
The process by which energy is released from food in a series of chemical reactions.
(1)
2.2
The study of interactions of organisms with one another and with the physical and chemical
environment.
(1)
2.3
The change in the structural, functional and behavioural characteristics of an organism.
(1)
(3 × 1) = [3]
3
Gr. 8 ~ Natural Sciences
March 2018
CONTEXTUAL QUESTIONS
QUESTION 3
The diagrams below show the relationship (interdependence) that exists between organisms. Study
the diagrams and answer the questions that follow.
Diagram A
Diagram B
Diagram C
3.1
What is the scientific term we use when referring to these specific relationships?
(1)
3.2
What kind of relationships is depicted by diagrams A, B and C respectively?
(3)
3.3
Which diagram indicates that one partner is benefiting while the other one is disadvantaged?
3.4
Fully describe the relationship between the organisms depicted in diagram A.
3.5
Study the following diagrams of different plant species.
Mushrooms
Water lily
(1)
(2)
Desert cactus
3.5.1 Identify a xerophyte.
(1)
3.5.2 Identify a hydrophyte.
(1)
3.5.3 Identify a fungus.
(1)
[10]
4
Gr. 8 ~ Natural Sciences
March 2018
QUESTION 4
The diagram below is a representation of a number of animal and plant species in a marine
ecosystem. Marine ecosystems are seawater ecosystems, with a much higher salt concentration than
freshwater ecosystems. A large variety of phytoplankton, which is microscopic plant material, forms the
basis of a marine food chain. Zooplankton are animal-like organisms feeding on the phytoplankton.
phytoplankton
92
zooplankton
69
pilchards
tuna
57
49
number of species
4.1
How many different organisms are found in total in the above-mentioned ecosystem?
(1)
4.2
Which species are the producers in this marine ecosystem?
(1)
4.3
Name two abiotic components in the marine ecosystem.
(2)
4.4
Do the organisms in the diagram form a community? Motivate your answer.
(2)
4.5
Draw a food chain of all the organisms in the diagram above.
(2)
4.6
Use the figures of the graph as a measure and draw a food pyramid to indicate the energy flow
in the marine community. Indicate the producers, primary, secondary and tertiary consumers in
the correct hierarchical order.
(4)
a
b
c
d
[12]
5
Gr. 8 ~ Natural Sciences
March 2018
QUESTION 5
The diagram shows a process that occurs in the leaf of a tree and other organisms containing
chlorophyll. Energy, water, and carbon dioxide are taken in by the leaf and oxygen and glucose are
produced.
CO2
energy
glucose
produced
oxygen released
water
5.1
Identify the process represented by this diagram.
(1)
5.2
What form of energy is taken in by the leaf?
(1)
5.3
Complete the simple chemical equation for the process.
(1)
Energy + H2O + ______ + ______ → ______ + ______
5.4
Compare the differences between photosynthesis and respiration in table form.
Name two points under each category.
(2)
[5]
TOTAL: 35
6
NATURAL SCIENCES
CONTROL TEST
GRADE 8
MARCH 2018
MEMORANDUM
TOTAL: 35
Gr. 8 ~ Natural Sciences Memorandum
March 2018
QUESTION 1
1.1
1.2
1.3
1.4
1.5
D
B
A
C
D





(5 × 1) = [5]
QUESTION 2
2.1
Respiration 
2.2
Ecology 
2.3
Adaptations 
(3 × 1) = [3]
QUESTION 3
3.1
Symbiosis 
(1)
3.2
A: Commensalism 
B: Parasitism 
C: Mutualism 
(3)
3.3
Diagram B 
(1)
3.4
Animal-plant → birds and trees; the birds build their nests in the trees. The trees provides
protection against predators and floods, so the birds benefits.
The tree is not at a disadvantage because of the nest, but it also does not benefit from this
relationship. 
(2)
3.5.1 Desert cactus 
(1)
3.5.2 Water lily 
(1)
3.5.3 Mushrooms 
(1)
[10]
2
Gr. 8 ~ Natural Sciences Memorandum
March 2018
QUESTION 4
4.1
4 
(1)
4.2
Phytoplankton 
(1)
4.3
Water,  sand,  rocks, shells (any two suitable components)
(2)
4.4
Yes;  there are various living organisms in one habitat. 
(2)
4.5
Phytoplankton → zooplankton → pilchards → tuna 
4.6
a) Tertiary consumer: tuna 
b) Secondary consumer: pilchards 
c) Primary consumer: zooplankton 
d) Producer: phytoplankton 
(2 or 0)
(4)
[12]
QUESTION 5
5.1
Photosynthesis 
5.2
sunlight (OR light OR light energy OR radiant energy OR solar energy) 
(1)
5.3
Energy + H2O + chlorophyll + CO2 → glucose + O2(g) 
(1)
5.4
Photosynthesis
Only takes place in plants. Respiration
Takes place in plants and animals. Oxygen and sugar are formed.
Needs sunlight.
Water and carbon dioxide are formed
during the process.
Does not need sunlight.
Food is produced.
Food is broken down.
Energy is stored.
Energy is released.
Only takes place in cells that contain
chlorophyll.
An anabolic (constructive) metabolic
process
Takes place in all living cells.
A catabolic (destructive) metabolic
process
 (any two correct answers) (2)
[5]
TOTAL: 35
3
NATURAL SCIENCES
PAPER
GRADE 8
JUNE 2018
EXAMINER: A. OelofseTOTAL: 70
MODERATOR: S. du Plessis
TIME: 1½ hours
INSTRUCTIONS
1. This paper has seven questions.
2. Answer ALL questions in this paper.
3. Number the answers according to the questions.
4. Carefully read through the paper before answering.
Gr. 8 ~ Natural Sciences
June 2018
QUESTION 1:
Multiple-choice questions
Each question has four possible answers. Choose the correct answer and write the
corresponding letter next to the question number, e.g. 1.11 D.
1.1
The diagrams below show the relationship between the numbers of producers and consumers
in two food chains:
Food chain 1:
producerprimary consumersecondary consumer
seeds and grass
rabbit
cat
seeds and grass
rabbit
cat
increasing number of individuals
Food chain 2:
producerPrimary consumerSecondary consumer
trees
caterpillars
birds
trees
caterpillars
birds
increasing number of individuals
Which of the following statements is supported by the information above?
In a food chain:
A.
there are more primary consumers than there are secondary consumers.
B.
there are more primary consumers than there are producers.
C.
primary consumers are larger than secondary consumers.
D.
primary consumers are usually insects that eat plants.
2
(1)
Gr. 8 ~ Natural Sciences
1.2
June 2018
How do decomposers obtain their food?
A.
Hunting and killing prey for food.
B.
Change carbon dioxide and water into food.
C.
Absorbing food from dead organisms.
D
Produce food from oxygen and sunlight.
(1)
Different species of carnivorous animals that share the same habitat in an ecosystem may:
A.
become decomposers.
B.
compete for food.
C.
produce their own food.
D.
mate with each other.
1.4
The graph below shows the relationship between the amount of light received by a plant and its
rate of photosynthesis:
(1)
rate of
photosynthesis
1.3
amount of light
As the amount of light received by this plant increases, its rate of photosynthesis:
A.
decreases then increases.
B.
decreases and then remains the same.
C.
increases then decreases.
D.
increases and then remains the same.
1.5
1.6
The process of cellular respiration:
A.
is performed only by organisms that are incapable of photosynthesis.
B.
breaks down food molecules to release stored energy.
C.
occurs before plants are able to carry out photosynthesis.
D.
occurs only in animals.
The following flow chart can be used to distinguish between some elements.
Element Y is sulfur and element X is carbon.
non-metal
gas
green
U
solid
colourless
inert
flammable
V
W
conductor
insulator
yellow
X
3
Y
not yellow
Z
(1)
Gr. 8 ~ Natural Sciences
June 2018
Which feature is used in the key to distinguish between them?
A.
Carbon is black and sulfur is yellow.
B.
Carbon is a conductor and sulfur is an insulator.
C.
Carbon is a gas and sulfur is not a gas.
D.
Sulfur burns with a flame and carbon glows red hot.
Study the four models that represent the
arrangement of atoms in four samples of
matter to answer Question 1.7 and 1.8.
Model
(1)
Arrangement of atoms
I
KEY
II
An atom of element X
An atom of element Y
III
IV
1.7
Which model best represents the arrangement of atoms in a solid?
A.
IB.
II
C.
IIID.
IV
1.8
Which model best represents the arrangement of atoms in a compound?
A.
IB.
II
C.
IIID.
IV
1.9
The reason why water cannot be used to extinguish an oil fire, is because:
A.
oil and water mix.
B.
water floats on oil.
C.
water is less dense than oil.
D.
oil floats on water.
1.10 Water (H2O) is not found on the Periodic Table of the elements because water is:
A.
an atom.B.
a liquid.
C.
a mixture.D.
a compound.
4
(1)
(1)
(1)
(1)
[10]
Gr. 8 ~ Natural Sciences
June 2018
QUESTION 2
Study the diagram and answer
the questions that follow:
sunlight
oxygen
carbon dioxide
chlorophyll
sugar
water
2.1
2.2
2.3
2.4
2.5
2.6
2.7
Which process is depicted by the diagram above?
In what way are people and animals favoured by the above-mentioned process?
What is the colour of chlorophyll?
Which part of the plant absorbs water from the soil?
Name the structures, found in the leaves, where absorption and release of gases (gas
exchange) takes place.
In which form is sugar produced during this process?
Why do the leaves of some trees turn brown during months of winter?
QUESTION 3
Study the diagram below of a specific
ecosystem. Answer the questions that
follow:
3.1
3.2
3.3
Which type of ecosystem is
represented here?
(1)
Name any:
3.2.1 TWO biotic components; (2)
3.2.2 TWO abiotic components.
(2)
Give an example from the diagram
of a:
3.3.1 producer;
(1)
3.3.2 herbivore;
(1)
3.3.3 carnivore.
(1)
5
(1)
(2)
(1)
(1)
(1)
(1)
(2)
[9]
Gr. 8 ~ Natural Sciences
3.4
3.5
June 2018
Use the diagram above and draw a food chain with a minimum of three organisms. (Only use
words.)
(3)
What will be the result if the balance between biotic and abiotic components is disturbed?
(1)
[12]
QUESTION 4
4.1
Use the picture in the table and identify the type of interdependence shown. Give a brief
description of the advantages and/or disadvantages of the interaction between the components.
Type of
interdependence
Photo
Description of interdependence
(advantages and/or disadvantages)
4.1.1
4.1.2
(1)
hermit crab
4.2
(2)
Study the photos below:
Draw a table and compare the adaptations of the ears and paws of the camel and the polar
bear.
(4)
4.3
Bacteria are found everywhere: in humans, animals, plants, soil, water and the atmosphere.
They are single-celled microorganisms. Examples: Salmonella enteritidis: causes food
poisoning. Streptococcus pyogenes: causes sore throat.
A.B.C.
Shape
Group/Type
.........................
Coccus
................................
Bacillus
..............................
Spirillium
4.3.1 Give the shape of each of these bacteria as can be derived from the photos above.
4.3.2 Give the name of the shape of bacteria B and C respectively.
6
(1)
(2)
Gr. 8 ~ Natural Sciences
June 2018
4.3.2 What is the function of the hair-like growth of bacteria?
4.3.3 Which microorganism is the smallest?
4.3.4 Name two diseases that are caused by the microorganism named in Question 4.3.3.
(2)
(1)
(2)
[15]
QUESTION 5
Consider the different states of water:
ABC
5.1
5.2
5.3
Write down only the letter (A, B or C) of the phase:
5.1.1 where the kinetic energy is greatest;
5.1.2 where particles only vibrate;
5.1.3 which can easily be compressed;
5.1.4 where the forces between the particles are the strongest.
Define the term diffusion.
In which phase will diffusion occur the fastest?
(1)
(1)
(1)
(1)
(2)
(1)
[7]
QUESTION 6
Study the following key of an element:
9
F
19
6.1
6.2
6.3
6.4
6.5
6.6
Classify the element as a METAL or NON-METAL.
Give the name of the group on the Periodic Table to which this element belong.
Calculate how many neutrons the element possesses.
The element reacts with sodium to form a product as shown in the reaction equation below:
2NA + F2 → 2NaF
Is this a SYNTHESIS REACTION or a DECOMPOSITION REACTION?
Give the name of the product.
Name the diatomic element in the reaction.
7
(1)
(1)
(2)
(1)
(1)
(1)
[7]
Gr. 8 ~ Natural Sciences
June 2018
QUESTION 7
Study the diagrams below:
O2
Na
C2H6
7.1
7.2
7.3
7.4
A BC
Write only A, B or C as answers. Which diagram/diagrams represents:
7.1.1 elements;
7.1.2 compounds;
7.1.3 molecules?
Which elements combine to form the content in diagram B?
Define the term density.
Identify the third densest material
from the substances shown:
(1)
(1)
(1)
(2)
(2)
ethanol
oil
water
dishwashing soap
glycerine
honey
7.5
(1)
The diagram represents how a learner is able to lift blocks of equal volumes that are
made of different materials:
ice
cork
7.5.1
7.5.2
iron
Describe one way that the learner can determine the exact volume of one of the three blocks.
(1)
Identify the property of the iron block that makes it more difficult to lift than the cork block.
(1)
[10]
TOTAL: 70
8
NATURAL SCIENCES
PAPER
GRADE 8
JUNE 2018
MEMORANDUM
TOTAL: 70
Gr. 8 ~ Natural Sciences Memorandum
June 2018
QUESTION 1
1.1
A 1.2
1.3
B 1.4
1.5
B 
1.6
1.7
A 1.8
1.9
D 1.10
C
D
B
C
D





[10]
QUESTION 2
2.1
Photosynthesis 
(1)
2.2
People and animals get food for energy to live. 
Oxygen is produced which allows people and animals to breathe. 
(2)
2.3
Green 
(1)
2.4
Roots 
(1)
2.5
Stomata 
(1)
2.6
Glucose 
(1)
2.7
There is less sunlight during winter, therefore less energy for trees to take in. 
(1)
It takes a lot of water and energy for trees to keep their leaves healthy. They have less of this
during winter. 
(2)
[9]
QUESTION 3
3.1
Desert 
(1)
3.2.1 Cacti; shrubs; vulture; jackal; owl; snake; scorpion; eagle; deer; rabbit; birds; tortoise; spider
(any two suitable answers) (2)
3.2.2 Soil,  rock,  air, light, mountain
(any two) (2)
3.3.1 Cactus,  shrubs
(any one) (1)
3.3.2 Rabbit,  tortoise, mouse, deer
(any one) (1)
3.3.3 Jackal,  snake, vulture, scorpion, spider, eagle, owl
(any one) (1)
3.4
Shrub  → mouse  → snake 
(any applicable answer) (3)
3.5
Organisms will become extinct. 
(1)
[12]
QUESTION 4
4.1.1 Commensalism 
(1)
4.1.2 The crab is favoured because it is protected by the shell. 
The shell is not impaired or favoured. 
(2)
4.2
Camel
Polar bear
Hair on inside of ears to keep sand
Small ears decrease the surface area from
Ears
out. 
which body heat can be lost. 
Bottom part of paw has a wide, flat, Large, wide paws, sharp claws and fur
leathery part – prevents it from
under their feet give a better grip on the
Paws
sinking into the sand. 
snow and protects them against cold through
insulation.
(4)
2
Gr. 8 ~ Natural Sciences Memorandum
June 2018
4.3.1 A: Round 
B: Rod-shaped 
C: Spiral-shaped 
4.3.2 To attach to the intestinal tract  and thus not to be flushed out. 
4.3.3 Virus 
4.3.4 HIV/Virus ; chicken pox ; measles; conjunctivitus
(3)
(2)
(1)
(any two) (2)
[15]
QUESTION 5
5.1.1 C 
5.1.2 A 
5.1.3 C 
5.1.4 A 
5.2
A process in which particles in liquids and gases move (separate and spread) from a
highly-concentrated  area to an area with a lower concentration of those particles. 
5.3
C
QUESTION 6
6.1
Non-metal 
6.2
Halogens 
6.3
n0 = 19 – 9  = 10n0 
6.4
Synthesis reaction 
6.5
Sodium fluoride 
6.6
Fluorine 
(1)
(1)
(1)
(1)
(2)
(1)
[7]
(1)
(1)
(2)
(1)
(1)
(1)
[7]
QUESTION 7
7.1.1 A, C 
7.1.2 B 
7.1.3 B, C 
7.2
Carbon  and hydrogen 
7.3
The amount of mass in a given volume of that material 
7.4
Dishwashing soap 
7.5.1 Length × width × height 
OR
Measure the amount/volume of water displaced.
7.5.2 - Density 
- Mass
- Weight
- It is heavier.
(1)
(1)
(1)
(2)
(2)
(1)
(1)
(any one) (1)
[10]
TOTAL: 70
3
NATURAL SCIENCES
CONTROL TEST
GRADE 8
SEPTEMBER 2018
EXAMINER: A. Oelofse
TOTAL: 35
MODERATOR: S. du Plessis TIME: 1 hour
INSTRUCTIONS:
1. This test consists of six questions.
2. Answer all the questions.
3. Number each question exactly as the test.
4. Carefully read through the test before you answer.
Gr. 8 ~ Natural Sciences
September 2018
QUESTION 1
Multiple-choice questions
Four possible answers are given for the following questions. Choose the correct answer and
write the letter next to the question number, i.e. 1.6 D.
1.1
1.2
A person experiences an electric shock when touching a metal doorknob. The particles
responsible for this shock are known as:
A.
atoms.B.
protons.
C.
neutrons.D.
electrons.
(1)
Choose the option from the given table that is NOT CORRECT.
Component
A. Light bulb
Symbol
B. Ammeter
A
C. Resistor
D. Switch
(1)
1.3
The separation of white light into colours, as shown
in the sketch, is known as:
A.
B.
C.
D.
1.4
dispersion.
diffraction.
refraction.
reflection.
A red filter:
A.
transmits green light.
C.
reflects green light.
(1)
B.
D.
absorbs green light.
emits green light.
2
(1)
[4]
Gr. 8 ~ Natural Sciences
September 2018
QUESTION 2
One-word items:
Give one word/term for each of the following descriptions.
2.1
2.2
2.3
2.4
The process when an electric current causes a chemical reaction in a solution.
Type of circuit that offers more than one route for the current to flow.
An object capable of breaking and focusing light.
Surfaces of objects/materials through which light cannot move.
(1)
(1)
(1)
(1)
[4]
QUESTION 3
Fit column A to Column B.
3.1
3.2
3.3
3.4
Column A
Objects acquire charges through:
Special wires that break the circuit when
overheated.
A(n) ___________ object reflects all the
frequencies/colours and therefore it looks
white.
In the eye, light energy is converted to:
Column B
A. Fuses
B. Black
C. Electrical nerve impulses
D. Copper wires
E. Friction
F. Magnetic nerve impulses
G. White
[4]
QUESTION 4
4.1
Electrostatic charge is important when aircrafts are refuelled. The most dangerous moment for
any aircraft is when it is refuelling.
fuel tank
fuel pipe
copper wire in ground
4.1.1 Electrostatic charge can build up as fuel is pumped through the fuel pipe. Explain how
this happens.
(2)
3
Gr. 8 ~ Natural Sciences
September 2018
4.1.2 Why is the build-up of electrostatic charge on the aircraft dangerous?
(1)
4.1.3 During refuelling a copper wire is attached between the wing and the ground. How does
this prevent the build-up of electrostatic charge on the wing?
(2)
4.2
Consider the following two spheres:
A
B
+
- -+
+ + - - -
+
- -+
+ + - - -
4.2.1 Determine the total charge on each sphere. Show your calculations.
(2)
4.2.2 Say if the spheres are positively charged, negatively charged or neutral. Give a reason
for your answer.
(2)
4.2.3 Redraw the spheres to show how the spheres will move due to the nature of the
charges.
(1)
[10]
QUESTION 5
Study the three series circuits.
All cells, light bulbs and resistors are identical.
Circuit A
Circuit B
R
5.1
5.2
5.3
5.4
Circuit C
R
R
Arrange the circuits from the one with the brightest light bulb to the one with the faintest light
bulb.
Explain your answer to Question 5.1.
Give the name of the instrument that can be used to measure the current in each circuit.
In which unit is resistance measured?
4
(2)
(2)
(1)
(1)
[6]
Gr. 8 ~ Natural Sciences
September 2018
QUESTION 6
6.1
Consider the picture of a ladybug sitting
on a green leaf:
6.1.1 Why does the ladybug look red?
6.1.2 Black is not a colour, yet we see black
spots on the ladybug. Explain how this
is possible by referring to reflection and
absorption.
6.2
(1)
(2)
Draw the following sketch on your answer sheet. Indicate how light is reflected from a rough
surface.
rough surface
6.3
Consider the diagrams below where a light beam moves from light through a rectangular prism
and moves back into air.
Diagram A
air
Diagram B
glass
block
6.3.1
6.3.2
glass
block
air
light ray
Diagram C
air
glass
block
light ray
light ray
Which of the above diagrams correctly indicates the path of a ray of light through a
rectangular glass prism?
(1)
Does the beam of light bend TOWARDS THE NORMAL or AWAY FROM THE NORMAL
when it enters the glass medium?
(1)
6.4
Redraw the following sketch. Complete the light rays to indicate which light is absorbed by the
filter and which light passes through.
(1)
[7]
red light
blue light
green light
green filter
TOTAL: 35
5
NATURAL SCIENCES
CONTROL TEST
GRADE 8
SEPTEMBER 2018
MEMORANDUM
TOTAL: 35
Gr. 8 ~ Natural Sciences Memorandum
September 2018
QUESTION 1
1.1
1.2
1.3
1.4
D
C
A
B




[4]
QUESTION 2
2.1
2.2
2.3
2.4
Electrolysis 
Parallel 
Lens 
Opaque 
[4]
QUESTION 3
3.1
3.2
3.3
3.4
E
A
G
C




[4]
QUESTION 4
4.1
As the fuel flows along the pipe, friction  between the fuel and the pipe will transfer
electrons  from one to the other.
4.2
There could be a discharge and a spark could ignite the fuel. 
4.3
The wire earths the wing.  This allows a transfer of electrons between Earth and the wing
which will neutralise the charge on the wing. 
4.2.1 Sphere A: (+4) + (-7) = -3 
Sphere B: (+4) + (-7) = -3 
4.2.2 Negatively charged;  excess electrons on each sphere 
4.2.3
A
+ +
- + + - - -
(2)
(1)
(2)
(2)
(2)
B
+ +
- + + - - -
(1)
[10]

2
Gr. 8 ~ Natural Sciences Memorandum
September 2018
QUESTION 5
5.1
5.2
5.3
5.4
A;  B;  C
With each addition of a resistor, the current decreases.  The less the flow of current, the
dimmer the light bulb. 
Ammeter 
Ohm  /Ω
(2)
(2)
(1)
(1)
[6]
QUESTION 6
6.1.1 When white light from the sun falls on the red cap of the ladybug, all the light is absorbed
except the red light.  The red light is reflected to our eyes and so we can see the red ladybug.
(1)
6.1.2 The black spots on the ladybug absorb all the colours  so that no light is reflected.  The
spots look black.
(2)
6.2
(1)
6.3.1 B 
6.3.2 Towards the normal 
6.4
(1)
(1)
red light
blue light
green light

green filter
(1)
[7]
TOTAL: 35
3
NATURAL SCIENCES
PAPER
GRADE 8
NOVEMBER 2018
EXAMINER: A. OelofseTOTAL: 70
MODERATOR: S. du Plessis
TIME: 1½ hours
INSTRUCTIONS
1. This paper has nine questions.
2. Answer ALL questions in this paper.
3. Number the answers according to the questions.
4. Carefully read through the paper before answering.
Gr. 8 ~ Natural Sciences
November 2018
QUESTION 1
Multiple-choice questions
Each question has four possible answers. Choose the correct answer and write the
corresponding letter next to the question number, e.g. 1.11 D.
1.1
Reflecting from a rough surface delivers:
A.
incident reflection.
B.
C.
broken reflection.
D.
1.2
The force responsible for creating static electricity is:
A.
frictional force.
B.
C.
applied force.
D.
dispersion.
scattered reflection.
(1)
gravitational force.
tensional force.
(1)
1.3
What effect of electric current is represented by an electromagnet?
A.
Chemical effect
B.
Electrical effect
C.
Heat effect
D.
Magnetic effect
1.4
The direction of electrical current flow (conventional current) is from the:
A.
north pole to the south pole.
B.
positive pole through the circuit to the negative pole.
C.
left to right.
D.
negative pole through the circuit to the positive pole.
1.5
A shooting star is a:
A.
comet.
B.
meteor.
C.
meteorite.
D.
star.
(1)
(1)
(1)
[5]
QUESTION 2
One-word items
Give one word/term for each of the following descriptions.
2.1
2.2
2.3
2.4
2.5
A perpendicular line that is on the surface between two optical levels.
Shining balls of gas in space, e.g. the sun.
The type of connection if only one electrical route is followed, and the current does not
divide.
The accumulation of electrical charges on an object without the charges moving.
Large dark holes on the moon
2
(1)
(1)
(1)
(1)
(1)
[5]
Gr. 8 ~ Natural Sciences
November 2018
QUESTION 3
Study the representations A–F and answer the questions:
A.
D.
B.
E.
C.
F.
For questions 3.1 to 3.5, write down only the letter of the representation.
3.1
... is an example of the heat effect of electric current.
3.2
... is an example where a photo cell delivers energy.
3.3
... shows the chemical effect of electric current.
3.4
... is an example of the magnetic effect of electric current.
3.5
... is a magnet that only works if electrical current flows through it.
3.6
Consider diagram B. What are two cells connected like this called?
3.7
Consider diagram F. Which city in South Africa had the first electric street lights?
3.8
Consider diagram F. What energy conversion takes place in the electric streetlight?
power source
QUESTION 4
Two learners are conducting an
investigation to determine whether
dissolved CuCℓ2(aq) will conduct
electricity.
ammeter
glass beaker
cathode
4.1
electrolyte
3
(1)
(1)
(1)
(1)
(1)
(1)
(1)
(2)
[9]
Gr. 8 ~ Natural Sciences
4.1
4.2
4.3
4.4
4.5
4.6
November 2018
Give the name of the electrode that is connected to the positive terminal of the battery.
As what are the negative ions in an electrolyte known?
What is the name of the electrolyte in the investigation?
Give the name of the brown metal that forms at the cathode.
What is the name of the gas that forms at the anode?
What energy conversion takes place during this experiment?
(1)
(1)
(1)
(1)
(1)
(1)
[6]
QUESTION 5
Two children jumping on a trampoline
notice that their hair starts to stand up.
5.1
5.2
5.3
5.4
What force between the children and the trampoline causes static electricity to be generated?
(1)
Use your knowledge of the particles of an atom and explain why the children’s hair is standing
upright.
(3)
The children touch the steel frame of the trampoline and notice a spark. What is this process
called?
(1)
What type of electrostatic force exists between a negative and a positive charge?
Write only ATTRACTIVE or REPULSIVE.
(1)
[6]
QUESTION 6
Consider the following circuit diagram and answer the questions that follow:
R
A
6.1
6.2
6.3
6.4
Identify the source of electrical energy in the diagram above.
Which unit is represented by the symbol Ω?
Complete the following statements by writing down the correct word between brackets.
6.3.1 If more cells are connected in series, the current will (increase/decrease).
6.3.2 If more resistors are connected in parallel, the overall resistance of the circuit will
(increase/decrease).
Draw the symbol of an open switch.
4
(1)
(1)
(1)
(1)
(1)
[5]
Gr. 8 ~ Natural Sciences
November 2018
QUESTION 7
Consider the diagram below, showing the path of a ray of light, and answer the questions that follow:
air
glass
air
7.1
7.2
7.3
•
•
•
Does the above sketch indicate the phenomenon of REFRACTION or REFLECTION?
(1)
What are substances called that allows light to pass through in order to clearly see the image
on the other side?
(1)
Copy the given sketch and indicate the following neatly on the sketch:
angle of incidence (θi);
angle of refraction (θr);
refracted ray.
(3)
[5]
QUESTION 8
8.1
White light which undergoes refraction,
displays a full spectrum of colours. The
violet light is refracted the most.
8.2
white light
8.1.1 Define dispersion.
(2)
8.1.2 Which light colour is refracted the least?
(1)
8.1.3 Give the name of the object used to separate white light.
(1)
8.1.4 Give an everyday example in nature where the refraction of white light is observed. (1)
Consider the following diagram where sunlight shines on a red apple and is observed by a
person:
8.2.1
8.2.2
8.2.3
8.2.4
What colour light is not absorbed by the apple’s skin?
(1)
What is the black dot called in the middle of a human eye?
(1)
Is the image falling on the retina UPRIGHT or UPSIDE DOWN?
(1)
Make a neat flow diagram to indicate the path of the red light beam through the eye to
the brain.
(5)
8.2.5 How is the eye protected from dust and sharp objects?
(1)
5
Gr. 8 ~ Natural Sciences
What will happen to the next two light rays
if they have to move through a BLUE FILTER?
Simply write down the number and choose:
ABSORBED, MOVING THROUGH or REFLECTED.
8.3.1 blue light
8.3.2 green light
blue filter
8.3
November 2018
(2)
[16]
QUESTION 9
The Southern African Large Telescope (SALT) is the largest single optical telescope in the Southern
Hemisphere and among the largest in the world. It has a hexagonal primary mirror array 11 meters
across, comprising 91 individual 1 m hexagonal mirrors.
SALT is situated at the South African Astronomical Observatory (SAAO) field station near the small
town of Sutherland, in the Northern Cape province, about 400 km from Cape Town. SALT is funded by
a consortium of international partners from South Africa, the United States, Germany, Poland, India,
the United Kingdom and New Zealand. The telescope has been in full science operation since 2011
and is realising its huge potential as Africa’s Giant Eye on the Universe.
Diagram A
Diagram B
9.1
9.2
9.3
9.4
9.5
Name three reasons why Sutherland is the most suitable place for SALT.
What human activity is detrimental to observation through earth telescopes?
Identify the diagram showing the SALT telescope. Write only A or B.
Give two reasons why South Africa works with a consortium of international partners?
Classify the type of telescope shown below:
9.6
Name two uses of artificial satellites.
(3)
(2)
(2)
(2)
(2)
(2)
[13]
TOTAL: 70
6
NATURAL SCIENCES
PAPER
GRADE 8
NOVEMBER 2018
MEMORANDUM
TOTAL: 70
Gr. 8 ~ Natural Sciences Memorandum
November 2018
QUESTION 1
1.1
D 
1.2
A 
1.3
D 
1.4
B 
1.5
C 
[5]
QUESTION 2
2.1
Normal 
2.2
Stars 
2.3
Series 
2.4
Static electricity 
2.5
Craters 
(1)
(1)
(1)
(1)
(1)
[5]
QUESTION 3
3.1
E
3.2
B
3.3
D
3.4
C / A
3.5
A
3.6
Series 
3.7
Kimberley 
3.8
Electrical energy to light & heat energy 
(1)
(1)
(1)
(1)
(1)
(1)
(1)
(2)
[12]
QUESTION 4
4.1
Anode 
4.2
Cations 
4.3
Copper(II) chloride 
4.4
Copper 
4.5
Chlorine 
4.6
Electrical energy to chemical energy 
(1)
(1)
(1)
(1)
(1)
(1)
[6]
QUESTION 5
5.1
Frictional force 
(1)
5.2
The friction that occurs during the contact  with the rubber mat, causes electrons to move
from the children to the trampoline.  Thus, the children are charged more positively and their
hair that is now similarly charged, pushes each other away. 
(3)
5.3
Discharge 
(1)
5.4
Attractive 
(1)
[6]
QUESTION 6
6.1
Cell/battery 
6.2
Ohm 
6.3.1 Increase 
6.3.2 Decrease 
(1)
(1)
(1)
(1)
2
Gr. 8 ~ Natural Sciences Memorandum
November 2018
6.4 
(1)
[5]
QUESTION 7
7.1
Refraction 
7.2
Transparent objects 
7.3
(1)
(1)
glass
θi
air
θr

air
refracted ray 
QUESTION 8
8.1.1 The breakup of white light into its constituent seven colours 
8.1.2 Red 
8.1.3 Glass prism 
8.1.4 Rainbow 
8.2.1 Red 
8.2.2 Pupil 
8.2.3 Upside down 
electrical
electrical
8.2.4





impulse
impulse
light
light
light
optic
pupil
lens
retina
brain
nerve
8.2.5 Eyelashes 
8.3.1 Move through. 
8.3.2 Absorbed 
(3)
[5]
(2)
(1)
(1)
(1)
(1)
(1)
(1)
(5)
(1)
(1)
(1)
[16]
QUESTION 9
9.1
Dark sky,  low rainfall,  high altitude,  cloudless night skies, minimum electromagnetic/
radio wave interferences, minimal pollution
(any three) (3)
9.2
Pollution 
(2)
9.3
B 
(2)
9.4
Funding is required. 
Academic experts from other countries’ valuable inputs 
(2)
9.5
Space telescope  (Hubble)
(2)
9.6
Weather satellites take photos to help with weather forecasts. 
Navigation 
Communication
Military espionage
(any two) (2)
[13]
TOTAL: 70
3