Science
2009 School Certificate Test
General Instructions
Total marks – 100
■
Reading time: 10 minutes
Section 1
■
Working time: 2 hours
Pages 2–24
■
Write using black or blue pen
■
You may use a pencil to draw
or complete diagrams
60 marks
Allow about 1 hour and 10 minutes for
this section
■
Attempt ALL questions
■
Calculators may be used
■
Detach the Stimulus Booklet
provided at the end of this paper
and use it where required
throughout the test
■
Write your Centre Number and
Student Number at the top of
pages 25, 27, 29, and 31
This section has TWO parts
Part A – Questions 1–50
50 marks
Part B – Questions 51–60
10 marks
Section 2
Pages 25–32
40 marks
Allow about 50 minutes for this section
This section has EIGHT questions
Question 61
5 marks
Question 62
6 marks
Question 63
2 marks
Question 64
3 marks
Question 65
5 marks
Question 66
7 marks
Question 67
5 marks
Question 68
7 marks
011
Section 1
60 marks
Allow about 1 hour and 10 minutes for this section
Part A
Questions 1–50
50 marks
Use the Section 1 Part A Answer Sheet for Questions 1–50
Instructions for answering multiple-choice questions
■
Select the alternative A, B, C or D that best answers the question. Fill in the
response oval completely.
Sample:
2+4=
(A) 2
A
■
(C) 8
B
C
(D) 9
D
If you think you have made a mistake, put a cross through the incorrect
answer and fill in the new answer.
A
■
(B) 6
B
C
D
If you change your mind and have crossed out what you consider to be the
correct answer, then indicate the correct answer by writing the word correct
and drawing an arrow as follows.
correct
A
B
C
– 2 –
D
1
What is the most appropriate piece of equipment to accurately measure 85 mL
of water?
(A) 10 mL measuring cylinder
(B) 100 mL measuring cylinder
(C) 100 mL beaker
(D) 250 mL beaker
2
What is one use for X-rays?
(A) Scanning barcodes
(B) Home alarm systems
(C) Operating remote controls
(D) Making images of skeletons
3
What is the smallest unit of an element?
(A) An atom
(B) An electron
(C) A neutron
(D) A proton
4
What does the word combustion refer to?
(A) The burning of a compound in oxygen
(B) A reaction that involves heat and smoke
(C) A reaction that involves hot acids and bases
(D) The flames that result when something burns
5
The chemical formula for limestone is CaCO3.
What information does the chemical formula give us?
(A) The type of atoms in the compound
(B) The size and mass of the compound
(C) The common name of the compound
(D) The arrangement of the atoms in the compound
–3–
6
Mobile phones use microwaves to send information to a transmitter.
What type of energy is used to carry the information from the mobile phone to a
transmitter?
(A) Electromagnetic
(B) Heat
(C) Light
(D) Sound
7
Six steps are involved in applying a scientific process to a problem. In the box
below, each step has been given a number, but the steps are not in the correct
sequence.
1
Gather experimental results
2
Draw a conclusion
3
Make a hypothesis
4
Compare experimental results with the hypothesis
5
Ask a question
6
Design and carry out an experiment
What is the correct sequence of steps?
(A) 1, 3, 6, 5, 4, 2
(B) 5, 3, 6, 1, 4, 2
(C) 5, 6, 3, 1, 2, 4
(D) 3, 5, 1, 6, 4, 2
– 4 –
Use the diagram to answer Questions 8–10.
Awaiting copyright
8
Which process involves plants using carbon dioxide?
(A) Burning
(B)
Decay
(C) Photosynthesis
(D) Respiration
9
Which processes add carbon dioxide to the atmosphere?
(A) Burning, decay and respiration
(B)
Burning, decay and photosynthesis
(C) Respiration, decay and photosynthesis
(D) Burning, photosynthesis and respiration
10
Organisms involved in decay are called decomposers.
What role do decomposers play in the carbon cycle?
(A) They provide food for animals.
(B)
They allow carbon to be reused.
(C) They limit the number of plants in an ecosystem.
(D) They remove carbon dioxide from the atmosphere.
– 5 –
Use the graph to answer Questions 11–12.
The graph shows the number of sunspots observed over a number of years.
200
150
Number
of
sunspots
100
50
1770 1780 1790 1800 1810 1820 1830 1840
Year
11
In which year were the most sunspots observed?
(A) 1770
(B)
1782
(C) 1789
(D) 1802
12
What is the approximate number of years between the peaks of the graph?
(A) 20
(B)
40
(C) 175
(D) 200
– 6 –
Use this information to answer Questions 13–14.
Some students carried out an experiment to determine what causes iron to rust. The
students placed iron into test tubes with different conditions and then sealed them.
The amount of rust formed was measured.
1
2
3
4
5
Rubber
stopper
Test
tube
Water
Strip
of iron
No oxygen
No water
13
Oxygen
No water
No oxygen
Water
Oxygen
Water
Which test tubes will show if water by itself will cause rusting?
(A) 1 and 3
(B)
2 and 3
(C) 3 and 4
(D) 1, 3 and 4
14
Oxygen
Water
Salt
What type of chemical reaction is rusting?
(A) Corrosion
(B)
Decomposition
(C) Neutralisation
(D) Precipitation
– 7 –
Refer to the diagram to answer Questions 15–17.
The diagram shows the distribution of plant communities in an ecosystem.
Plant Communities
Height above sea level (m)
40
35
Woodland
Bare
rock
Closed heath
Woodland
Area
V
Area
W
Area
X
Area
Y
Closed forest
30
25
20
15
10
5
0
Area
Z
50 100 150 200 250 300 350 400 450 500 550 600 650 700 750 800 850
Distance (m)
Woodland
eucalypt
Key
Forest
eucalypt
Ferns
Shrubs
Grass
Reproduced by permission of Oxford University Press Australia, www.oup.com.au The Spectrum of Life, 2nd Ed
15
What is the best way to record the numbers and types of plants found in each
area?
(A)
(B)
Type of plant
community
Area
Area
Type of plant community
(C)
(D)
Area
W
Area
V
Area
V
W
Area
Y
Area
Z
X
Area
X
Y
Z
–8–
Number of plants
16
What is the height of the tallest eucalypt?
(A) 18 m
(B)
26 m
(C) 34 m
(D) 840 m
17
Which area of the ecosystem shows ONLY abiotic features?
(A) W
(B)
X
(C) Y
(D) Z
18
The diagrams show two equal forces acting on a 10 kg mass in different ways.
Which arrangement of forces will lead to the greatest acceleration of the 10 kg
mass?
(A)
(B)
Mass
Mass
Key
Direction of force
(C)
(D)
Mass
19
Mass
What is the chemical formula for carbon dioxide?
(A) CO2
(B)
CO
(C) C2O
(D) CO2
–9–
Use this information to answer Questions 20–21.
Students set up an experiment to see how temperature affects a chemical reaction.
Four 2 cm strips of magnesium were placed into four test tubes of acid at different
temperatures as shown.
1
2
3
4
Acid
Magnesium
strip
10°C
20°C
30°C
40°C
The students timed in seconds how long it took for the magnesium to dissolve. The
results are shown in the table.
20
Test tube
1
2
3
4
Temperature (°C)
10
20
30
40
Time (s)
40
30
20
10
Which alternative correctly identifies the independent and dependent variables
in the experiment?
Independent variable
Dependent variable
(A)
Time
Temperature
(B)
Amount of magnesium
Time
(C)
Temperature
Time
(D)
Temperature
Amount of magnesium
– 10 –
Which graph best represents the results of the experiment?
50
Temperature (°C)
(A)
50
(B)
40
Temperature (°C)
21
30
20
0
2
3
Test tube
4
50
Temperature (°C)
30
20
10
1
2
3
Test tube
10
20
30
Time (s)
40
30
20
10
0
0
10
20
30
40
Temperature (°C)
The diagram shows a DNA molecule.
P
What is the name of the section labelled P on the DNA molecule?
(A) Base
(B)
4
50
(D)
40
Time (s)
20
0
1
22
30
10
10
(C)
40
Chromosome
(C) Gene
(D) Nucleus
– 11 –
40
Use the flowchart to answer Questions 23–25.
The process of making wine is outlined in the flowchart.
Awaiting copyright
23
Which wines are fermented completely before bottling?
(A) Red wine and dry white wine
(B)
Red wine and sweet white wine
(C) Dry white wine and sweet white wine
(D) Dry white wine and sparkling white wine
24
What is an advantage of presenting information in a flowchart?
(A) It shows trends in data.
(B)
It shows how much of each product is made.
(C) It shows the sequence of steps in the process.
(D) It shows the length of time involved in each step.
25
Why is fermentation an example of biotechnology?
(A) The products can be consumed.
(B)
Grape vines are a renewable resource.
(C) Living things are used in this process.
(D) Living things are not harmed in this process.
– 12 –
Refer to the diagram to answer Questions 26–27.
The diagram shows a chemical compound.
Key
H
O
S
26
What is the chemical formula of the compound?
(A) S2OH
(B)
H4OS2
(C) H2SO4
(D) OH2S4
27
Which element is represented by the symbol
?
(A) Halogen
(B)
Helium
(C) Hydrogen
(D) Hydroxide
28
Which two scientists are given credit for describing the structure of DNA?
(A) Darwin and Wallace
(B)
Fleming and Florey
(C) Newton and Mendel
(D) Watson and Crick
– 13 –
Use this information to answer Questions 29–30.
A student heated some copper carbonate in a test tube as shown.
The student wrote the following notes in their note book.
1 The solid changed colour from green to black.
2 Carbonates release carbon dioxide gas when heated.
3 The gas collected turned limewater a milky colour.
4 The black solid must be carbon.
29
Which statement about the notes is correct?
(A) Note 2 is a hypothesis.
(B)
Note 4 is an observation.
(C) Notes 1 and 4 are conclusions.
(D) Notes 1, 2 and 3 are observations.
30
Why is the reaction called a decomposition reaction?
(A) Heat is required.
(B)
Carbon dioxide is produced.
(C) Two substances combine to form a larger molecule.
(D) One reactant breaks down into two or more products.
– 14 –
The circular key is used to identify some ores.
Spha
lerite
na
Gale
k
Scr
kni atch
fe
bla e
d
Meta
llic
l
Py
rite
Pal
e
Cry gold
co
st
be als m lo
vis
ibl ay
e
ur
olo
c
ed
or
e r , red
g
an nge treak
ra n s
w
ro
by
ed
h
il
tc
ra erna
g
n
Ma
l
a
c
hit
e
B
r
i
gh
tg
r
c
Gre olou een
en
r
s
tre
a
S
fi
Sc
knife blade
by a
b
O
e
ht blu
Brig
r
u
colo
eak
e str
Blu
Orange
brow
n
c
Y
o
e
l
l
o
lou
w
-bro
r
wn
strea
k
rite
Azu
Or
ite
ux
a
B
Magnetite
Black colour
Scratches a
streak plate
Start here
Scratches
knife blade
Scratched by
knife blade
tre
us
nd
llic a
eta r thy
a
ye
Golden colour
Tarnishes to
purple
e
m
Chalcopyrite
Scratch
ed b
y
knife b
lade
Sa
as
Par
tly
pa
rtl
m
s
d
atche
Scr
oin
by c
ed
tch
cra
ur
te
ati
em
Ha
rey
rg
d o ur
Re colo eak
r
t
ds
s
Re
nes
ard de
e h e bla
if
kn
Black
colo
Brow ur
n
strea
k
colour
ery
v
l
i
S
eak
y str
Gre
avy
y he
Ver
ll ear thy lustre
Du
Limo
nite
31
A particular ore is described as partly metallic and partly earthy. It is easily
scratched by a knife blade and it has a brown streak.
What is the name of the ore?
(A) Haematite
(B)
Limonite
(C) Magnetite
(D) Sphalerite
– 15 –
Refer to the chart to answer Questions 32–33.
The chart shows the range of frequencies that some musical instruments can produce.
Frequency (Hz)
0
100
200
300
400
500
600
700
800
900
Timpani
Tuba
Trumpet
Double bass
French horn
32
Which instrument has the smallest frequency range?
(A) Double bass
(B)
French horn
(C) Timpani
(D) Tuba
33
Which frequency can be produced on four of the five instruments?
(A) 100 Hz
(B)
325 Hz
(C) 400 Hz
(D) 750 Hz
34
What is the frequency of a wave?
(A) The speed of the wave
(B)
The direction of the wave
(C) The distance between wave crests
(D) The number of vibrations each second
– 16 –
1000
35
This key can be used to identify particles.
Key:
1 (a) Has 1 nucleus …………………………………………………………… go to 2
(b) Has 2 nucleii …………………………………………………………… Molecule
2 (a) Has equal numbers of protons and electrons ………………… Atom
(b) Has different numbers of protons and electrons …………… go to 3
3 (a) Has more electrons than protons ………………………………… Anion
(b) Has more protons than electrons ………………………………… Cation
A diagram shows an unidentified particle.
Using the key, what sort of particle is shown?
(A) Anion
(B)
Atom
(C) Cation
(D) Molecule
36
What is an advantage of DNA mutating?
(A) DNA is altered.
(B)
Mutations cause deformities.
(C) Mutations give rise to variation.
(D) DNA mutations are essential for transportation of materials.
37
When cells divide to replace dead skin cells the DNA is replicated exactly.
What advantage does this give the new cells?
(A) They will be more resistant to ultraviolet light.
(B)
They will last longer than the ones they replace.
(C) They will be stronger than the ones they replace.
(D) They will perform the same functions as the ones they replace.
– 17 –
38
10
15
5
0.5
1.0
1.5
0
20
0
2
–
2
20
What is the reading on the voltmeter?
(A) 0.52 V
(B)
0.6 V
(C) 5.2 V
(D) 6.0 V
Refer to Source A in the Stimulus Booklet to answer Questions 39–42.
39
What do we call the bending of light that is occurring at Point A?
(A) Absorption
(B)
Reflection
(C) Refraction
(D) Transpiration
40
What is the most accurate description of SLIVER® solar technology?
(A) A new biotechnology
(B)
A new scientific theory
(C) A non-renewable technology
(D) An application of an existing technology
– 18 –
41
The individual pieces of silicon in a SLIVER® cell are arranged in a series circuit.
Which diagram shows all the SLIVER® cells arranged in a series circuit?
SC
(A)
(B)
SC
SC
SC
SC
SC
SC
SC
SC
(C)
(D)
SC
SC
SC
SC
SC
SC
SC
SC
SC
Key
42
SC
SLIVER® cell
Wire
Mobile telephone
The diagram shows the waves that make up the electromagnetic spectrum.
10–13
10–11
10–9
10–7
10–5
10–3
10–1
101
103
(metres)
105
Increasing wavelength
Gamma rays
Radio
X-rays
UV rays
Infra-red
Visible
Light
What is the approximate wavelength (in metres) of the waves that can be used to
produce electricity from SLIVER® cells?
(A) 10–10
(B)
10–7
(C) 10–5
(D) 10–1
– 19 –
Refer to Source B in the Stimulus Booklet to answer Questions 43–47.
43
Which drink has the highest concentration of calcium salts?
(A) Bottled water
(B)
Pineapple/orange drink
(C) Soft drink
(D) Sports drink
44
Which drink contains equal concentrations of potassium salts and calcium salts?
(A) Bottled water
(B)
Pineapple/orange drink
(C) Soft drink
(D) Sports drink
45
How many milligrams of potassium salts are found in 200 g of sports drink?
(A) 15
(B)
30
(C) 40
(D) 80
46
47
Which option correctly describes what happens to salts in the body?
Salts enter the blood from
Salts are removed from the blood in
(A)
Small intestine
Bladder
(B)
Large intestine
Bladder
(C)
Small intestine
Kidney
(D)
Large intestine
Kidney
How did Student 2’s time for the run change from Day 1 to Day 2?
(A) It increased by 5 seconds.
(B)
It decreased by 30 seconds.
(C) It increased by 15 seconds.
(D) It decreased by 20 seconds.
– 20 –
Refer to Source C in the Stimulus Booklet to answer Questions 48–50.
48
What is the highest setting on the volume control of a MP3 player that is unlikely
to cause hearing loss?
(A) 40%
(B) 65%
(C) 80%
(D) 100%
49
What is the minimum loudness of a 2000 Hz sound that person Y can hear?
(A) 0 dB
(B) 40 dB
(C) 50 dB
(D) 70 dB
50
Person Y played their MP3 player at the loudness of a normal conversation.
Which frequencies can they hear?
(A) All
(B) None
(C) Less than 4000 Hz
(D) Greater than 4000 Hz
– 21 –
Section 1 (continued)
Part B
Questions 51–60
10 marks
Use the Section 1 Part B Answer Sheet for Questions 51–60
Instructions for answering Questions 51–60
■
Write firmly and clearly.
■
Use BLOCK LETTERS for words.
Like this:
NOT like this:
A L P H A B E T
a
l
p h a b e
t
✔
✘
■
Numbers must be used for numerical answers.
■
Decimal points and negative signs must be clearly shown in separate boxes.
■
Do NOT let any part of the letter or number touch the sides of the answer
boxes.
■
Examples:
■
–7 ÷ 2 =
– 3
How many days are in a week?
7
What is the fifth month?
M A Y
.
5
If you make a mistake, cross out the incorrect answer and write the correct
answer above the boxes.
M A Y
Like this:
J U N E
– 22 –
Refer to the following graph to answer Questions 51–53.
The graph represents a student’s progress walking from school to home over
20 minutes.
900
800
700
600
Distance
from
school
(metres)
500
400
300
200
100
0
2
4
6
8
10 12 14
Time (minutes)
16
18
20
51
How many metres did the student travel to get home?
52
How many times did the student stop during the journey?
53
What was the student’s average speed for the first 4 minutes in metres per
minute?
speed =
distance
time
Please turn over
– 23 –
54
Name the element that is present in both hydrochloric acid and sulphuric acid.
55
What is the name given to the current scientific theory to explain how the
universe began?
56
Within Earth, magma is heated causing it to rise. It then cools and sinks.
What is the name given for this type of movement of magma?
57
What is the name of the group of substances that are used to determine if a
solution is basic or acidic?
58
What name do we give to any type of disease that can be passed from one person
to another person?
Refer to Source A in the Stimulus Booklet to answer Question 59.
59
What term is used to describe the behaviour of light at point B on the diagram?
Refer to Source C in the Stimulus Booklet to answer Question 60.
60
Ear muffs must be used when operating a jack hammer. By how many decibels
must the loudness of sound be decreased to prevent hearing loss?
– 24 –
© Board of Studies NSW 2009
012
5020
8329310040
2009 School Certificate Test
Science
Centre Number
Section 2
Student Number
40 marks
Allow about 50 minutes for this section
Questions 61–68
40 marks
Answer the questions in the spaces provided.
Question 61 (5 marks)
Refer to Source B in the Stimulus Booklet to answer this question.
This divided bar graph shows the percentage composition of dissolved salts
in blood.
Potassium (1.5%)
Calcium (3.5%)
Sodium (54%)
Other (41%)
(a) Construct a divided bar graph to show the percentage composition of
dissolved salts in urine.
3
(b) There are two systems involved in coordinating the functioning of the
human body.
2
Describe the role that each of these systems plays in maintaining humans
as functioning organisms.
...............................................................................................................................
...............................................................................................................................
...............................................................................................................................
...............................................................................................................................
– 25 –
3146310042
Question 62 (6 marks)
Refer to Source B in the Stimulus Booklet to answer this question.
(a) Name ONE variable that was held constant in the students’ experiment.
1
...............................................................................................................................
(b) Outline TWO features of the scientists’ experiment that show they have
followed correct experimental method.
2
...............................................................................................................................
...............................................................................................................................
...............................................................................................................................
...............................................................................................................................
(c)
What conclusion can be drawn from the scientists’ experiment?
1
...............................................................................................................................
(d) How can the processes used in science help us make informed judgments
about claims made in the mass media?
...............................................................................................................................
...............................................................................................................................
...............................................................................................................................
...............................................................................................................................
– 26 –
© Board of Studies NSW 2009
2
013
5020
8432310089
2009 School Certificate Test
Science
Centre Number
Section 2 (continued)
Student Number
Question 63 (2 marks)
Refer to Source C in the Stimulus Booklet to answer this question.
There is a proposal to limit the loudness of MP3 players to less than 80 dB.
2
Explain why this proposal would benefit MP3 users or the rest of society.
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
Question 64 (3 marks)
The diagrams illustrate the effect of gravity on a 70 kg astronaut on the Moon
and on Earth. The size of the arrows is an indication of the difference in
gravity (newtons) at each place.
Awaiting copyright
Referring to the diagram, distinguish between the terms mass and weight.
........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
– 27 –
3
5391310080
Question 65 (5 marks)
A teacher used this dessert to model the geological history of sediments at a particular
place.
Red jelly
Chocolate
Orange jelly
Marshmallow
Yellow jelly
Jelly bean
Green jelly
(a) How could this dessert be used as a model to explain how geological
history is interpreted?
2
...............................................................................................................................
...............................................................................................................................
...............................................................................................................................
...............................................................................................................................
(b) What geological reason could the teacher use to explain the absence of
lollies in the bottom layer of jelly?
1
...............................................................................................................................
...............................................................................................................................
...............................................................................................................................
(c)
Outline ONE advantage and ONE limitation of using this model to
illustrate geological history.
Advantage ..........................................................................................................
...............................................................................................................................
...............................................................................................................................
Limitation ...........................................................................................................
...............................................................................................................................
...............................................................................................................................
– 28 –
© Board of Studies NSW 2009
2
014
5020
7046310090
2009 School Certificate Test
Science
Centre Number
Section 2 (continued)
Student Number
Question 66 (7 marks)
(a) Complete the flowchart to summarise the process of natural selection
and its effect on a species. Use as many boxes as you require.
More offspring are
produced than needed
to replace the parents
Variation within
the population
Question 66 continues on page 30
– 29 –
4
1445310097
Question 66 (continued)
(b)
Name a scientific theory and explain how a specific piece of evidence
supports this theory.
...............................................................................................................................
...............................................................................................................................
...............................................................................................................................
...............................................................................................................................
...............................................................................................................................
...............................................................................................................................
End of Question 66
– 30 –
© Board of Studies NSW 2009
3
015
5020
2612310106
2009 School Certificate Test
Science
Centre Number
Section 2 (continued)
Student Number
Question 67 (5 marks)
The diagram shows the human reproductive systems.
Male reproductive system
Female reproductive system
Y
Z
X
(a)
Complete the table for the organs labelled X and Y.
Name of organ
3
One function that both organs X and Y perform
X
Y
(b)
Identify the organ labelled Zand describe its reproductive function.
...............................................................................................................................
...............................................................................................................................
...............................................................................................................................
...............................................................................................................................
Please turn over
– 31 –
2
7660310104
Question 68 (7 marks)
Some alternative energy sources are nuclear energy, wind energy and solar
energy.
Evaluate the environmental impacts of replacing fossil fuels with alternative
energy sources.
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
.........................................................................................................................................
End of test
– 32 –
© Board of Studies NSW 2009
7
2009 School Certificate Test
Science
Stimulus Booklet
Detach this Stimulus Booklet and use it where required during the test.
Source A – Solar Cell Technology
Awaiting copyright
016
– 1 –
Source B – Sports Drinks
Many people believe that sports drinks can improve their athletic performance. The main
components of these drinks are carbohydrates and salts (sodium, potassium and calcium).
The graph shows the concentration of salts found in some drinks.
Concentration of salts found in some drinks
50
Key
45
Sodium salts
Concentration (mg /100 g)
40
Potassium salts
35
Calcium salts
30
25
20
15
10
5
0
Sports drink
Soft drink
Pineapple/orange
drink
Bottled water
Drink type
What happens to sports drinks in the body
Sports drinks are absorbed by the digestive system and excess salts are removed by the
urinary system.
Digestive system
Urinary and nervous systems
Brain
Pituitary gland
Mouth
Spinal cord
Stomach
Adrenal gland
Kidney
Bladder
Carbohydrates enter the
blood from the small intestine.
Some salts enter the blood
from the large intestine.
Dissolved salts in urine
The kidney filters the blood to produce urine.
The dissolved salts in urine are: potassium
(45%), sodium (20%), calcium (8%) and
other substances (27%).
– 2 –
Source B – Sports Drinks (continued)
Some students found the following advertisement.
Guarantee your performance
Our research shows that Sports 4 U
improves athletic performance by 10%.
Sports
350 mL
They tested the effectiveness of Sports 4 U at improving athletic performance. They used
this method:
1.
Two students drank 350 mL of water and then ran one km. The run was timed.
2.
The next day, the same two students drank 350 mL of the sports drink instead of
water and then ran one km. The run was timed.
These were the students’ results.
Time
DAY 1 – water
DAY 2 – sports drink
Student 1
5 min 45 sec
6 min
Student 2
5 min 50 sec
5 min 30 sec
During their research they discovered that scientists had carried out a similar experiment
using 500 16-year-olds of the same athletic ability.
These were the scientists’ results:
Time
Average
times
DAY 1 – water
DAY 2 – sports drink
5 min 29 sec
5 min 30 sec
– 3 –
Source C – Sound Intensity and Hearing Loss in Humans
The loudness of sound is measured in units called decibels (dB). Repeated exposure to any
sound with a loudness above 80 dB can lead to hearing loss.
This table describes sounds of different loudness.
Loudness
(dB)
Description
0
Softest sound that can be heard with normal hearing
30
Quiet country road
60
Normal conversation
100
Jack hammer
130
Sound at this loudness causes pain to the listener
People who use MP3 players at a loudness above 80 dB can experience hearing loss.
Graph 1
shows the loudness of an MP3 player (in dB) for different settings on the volume
control.
Graph 1
Loudness of MP3
players (dB)
120
100
80
60
40
20
0
0
20
40
60
80
Volume control setting (%)
100
shows the frequencies that a person with normal hearing and a person with a
hearing loss can hear at different levels of loudness.
Graph 2
Graph 2
Loudness of sound (dB)
Soft
Loud
X
0
10
20
Person X with normal hearing
is able to hear frequencies at
levels of loudness indicated
below this line
30
40
50
60
70
80
250
Y
500 1000 2000 4000 8000
Person Y with hearing loss is able
to hear sounds with levels of
loudness and frequencies as
indicated in the shaded area
Frequency (Hz)
–4–
© Board of Studies NSW 2009