Deconstructing Exam Questions

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Deconstructing Exam Questions
LAZSTA
2010
Greg Pitt
Changes to the HSC beginning in 2010
Section I
Part A
Part B
20 marks – 20 multiple choice (Note this change)
55 marks – Written response (Extended answer)
Section II
25 marks – Option (one from the following)
- Polymers
- Preservatives and Additives
- Pharmaceuticals
- Disasters
- Space Science
HSC Timetable 2010
 Download from http://www.boardofstudies.nsw.edu.au/events/
BOS – Important notice
Question 19 (2009 HSC)
HSC Outcomes – A student…
Outcomes-related questions [Outcome H2]
(a) Explain the effect
of pulling down
on the rubber
sheet. (2M)
(b) Outline why
models, such as
the one shown,
are used in
science. (2M)
Outcomes-related questions [Outcome H2]
(a)
(b)
Explain the effect of pulling down on the
rubber sheet. (2M)
Outline why models, such as the one
shown, are used in science. (2M)
HSC 2009
Question 20 (6 marks)
Describe the beneficial and detrimental effects of soaps and
soapless detergents on the environment. (6M)
HSC 2009
Question 20 (6 marks)
Describe the beneficial and detrimental effects of soaps and
soapless detergents on the environment. (6M)
HSC 2009
Question 27 (6 marks)
A fax machine firstly converts an image into information. The information is
transmitted through a copper wire and then transmitted using an optical fibre.
Describe the processes that take place at each of these three steps.
HSC 2009
Question 27 (6 marks)
A fax machine firstly converts an image into information. The information is
transmitted through a copper wire and then transmitted using an optical fibre.
Describe the processes that take place at each of these three steps.
Sample answer:
The document is scanned by a beam of light along very thin lines. The light
reflects differently from different marks on the page. The reflected light is
detected by a photocell. The photocell converts the incident light into
electrical voltages. This signal carriers information along a copper wire. For
optical fibre, the electrical energy is converted to light for transmission, and
the signal is digitally encoded.
HSC 2008 – Question 23
Discuss the use of visible light in communication systems.
(6M)
HSC 2008 – Question 23
Discuss the use of visible light in communication systems.
(6M)
Visible light can be used in simple communication systems such as traffic lights
and lighthouses.
The advantages of using light in such communication systems are that light
travels at very high speeds and the information is sent virtually
instantaneously.
The ability of light to be reflected allows the information to be sent through
underground cables between the source and destination.
One disadvantage of light is that it cannot always be used to transmit
information through the atmosphere during the day due to interference with
natural light. This is why lighthouses only operate at night-time.
HSC 2007 – Question 19
Question 19 (5 marks)
Relate the properties of pesticides and body hygiene
products to the precautions needed when using and
handling each type of chemical.
Notes from the markers: Better responses identified
precautions to follow when using both these types of
chemicals and then related them to specific properties of
pesticides and of body hygiene products.
The weakest responses only included precautions with little
or no mention of properties of either type of chemical.
HSC 2007 – Question 24 (b)
Explain reasons for the increased use of fibre optics in
communication. (4 marks)
Reasons – two examples
Greater data carrying capacity
Reduced cost (per megabyte of data)
Explanation
Greater data carrying capacity is possible because using light (IR),
it is possible to switch the light on and off (hence binary code) at
extremely high frequencies and hence more data bits per second.
Reduced cost (per megabyte of data) has happened because
each fibre can carry more data per second and many fibres can
be laid simultaneously at little extra cost (redundancy for future).
HSC 2007 – Question 25
Relate TWO properties of microwaves to their use in
communication through air and space. (4 marks)
Two properties of microwaves
Travel very fast – at the speed of light
Travel through a vacuum as well as the air
Relationship between property and use
Travel very fast – this makes almost instantaneous
communication possible between points on Earth and to/from
satellites in orbit around the Earth.
Travel through a vacuum as well as air – this makes it possible to
communicate using satellites as well as through the air making
mobile phone communication possible.
HSC 2007 – Question 27
Assess the impacts that changes in communication systems
have had on society. (6 marks)
HSC 2006 – Question 18 (b)
Explain why knowledge of the solubility of materials is important
to the way medications are administered. (4 marks)
HSC 2006 – Question 26
Technological advances have enabled human
communication to change from methods that were mainly
used over short distances, to a range of systems that allows
worldwide communication to occur.
Analyse the relationship between the development of
worldwide communication systems and the changes that
these systems have produced in society. (7 marks)
Mandatory First-hand Investigations
• perform a first-hand investigation to observe ways in which waves
can be modulated to carry different types of information
(Syllabus dot point)
Q27 2002 HSC
Mandatory Investigations
• perform a first-hand investigation to observe ways in which waves can be
modulated to carry different types of information (Syllabus dot point)
Deconstructing a Question
Relate cause and effect;
make the relationships
between things evident;
provide why and/or how
Satellite dedicated to
sending of information
between two points on
the Earth
Altitude, distance
above the Earth’s
surface
Explain why a communications satellite
must be at a height at which its
revolution period is the same as that of
the Earth’s period of rotation
Time taken to
travel once
around the
Earth, also
called the
orbital period
equal
Time taken for the Earth
to rotate once on its
axis, axial rotational
period, 24 h
Other Useful Resources (for Biology teachers)
 Casseopiea Evolution http://www.cassiopeiaproject.com/videos2.php
(Download from iTunes)
(Or from YouTube) http://www.youtube.com/watch?v=Hzx2F8fqyEA
This is an excellent series of 6 programs about evolution and other topic areas
are available.
Download