TRANSFORMING PEDAGOGIES WITH NEW TECHNOLOGIES
Simple Machines
Year 7
Marissa Novak
Launceston Church Grammar School (TAS)
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Thinking and Planning
Purpose
The main reason I chose this particular topic was because I do not like teaching it. I don’t know a great deal about simple
machines and I often do not do the teaching of it any justice. Therefore, I thought that if I could find some good
supplementary material to help me, the job would not so difficult whenever it came to teaching this topic. I also feel that some
students learn best in a self-paced condition where they can go back and re-visit an activity over and over until they
understand what they need to do or what the correct answers are.
There are many ideas as to what can be included in the unit of work: students can bring their bikes in for everyone to have a
look at the gears and bike speeds, a bike track can be set up with hills, etc., to test best and correct gear choices, the school
flag pulley system can be used to test the best arrangement, cars can be bogged and an attempt made to pull them out with
winches and trees, and so on.
Learning Outcomes
The intended learning outcomes are for students to be able to understand the importance of everyday use for simple
machines, where they have used them and how they work (including levers, wheels, pulleys, gears, inclined planes, etc).
Digital Content
In this unit the digital content will be linked by either TLF learning objects or internet research (perhaps in the form of
webquests). This will enable students to become literate in certain key terms associated with the different types of simple
machines studied, and enable them to use computers to experiment with different variables (TLF learning object L481 Wild
Ride: in top gear shows this with gears). This particular digital content will be used as a pre-test or introductory lesson to the
topic of gears to see what students know or allow students to self-pace their learning. Similarly, TLF learning objects L1198
Pulleys, L1201 Pulleys: lifting challenge and L4059 Lifting loads: force will provide an introduction and then reinforce
knowledge and skills learnt when investigating the impacts of the successful use of pulley systems.
The particular learning objects used were selected based on their year level and length of time needed to complete them.
For example, L481 Wild Ride: in top gear required a longer lesson to complete the activity, which meant that skills and ideas
were reinforced over a longer period of time, rather than just a quick demonstration of how gears work. It allows students to
spend time looking at the history of gears, why they are useful, how they use them in their lives (always the question asked
by adolescents: “But, when will we ever use this information?”). It shows real-life implementation of knowledge and skills.
The topic of simple machines has always been one that is left until the end of the last term as an ‘if we get to it’ unit. More
often than not it is left out as too hard and something else is always taught in its place. This may have been because there
were very few quality resources available for teachers, or teachers were just not comfortable in their understanding of the
topic in order to do it justice in the classroom; which is why the topic of simple machines was chosen for this unit. TLF
learning objects used in this unit should at least give teachers a starting-off point for some topics (gears and pulleys). For
those teachers who already teach this unit well, the learning objects should enhance the learning of the students.
One of the reasons the learning objects were chosen is that they allow students to have a conceptual understanding of the
ideas and concepts. A work sheet will be provided for each learning object to actually test for a transfer of knowledge, as well
as follow-up activities and testing (whether these are done as informal discussions or formal assessment tasks is not
finalised).
Since the majority of students will be unfamiliar with any of the scientific concepts behind the simple machines unit, the
learning activities and learning objects used should allow for students to be engaged at the various stages of the process of
scientific inquiry. Perhaps a small research project at the end of the unit could be an assessment task to test for the final
stage of scientific inquiry.
Students are always asked to relate what is being taught to where they use them in real life. The specific learning objects in
the unit have characters of a similar age to the students in the class and activities (like a bike race) that students can relate to
very easily. Therefore, it should enhance their interest in the topics and hopefully help them learn when they don’t realise
that they are learning (always a good thing).
Of course, different teachers will use different methods to assist students. All students will be at different stages in their
scientific understanding, ICT literacy and computer skills. Therefore, depending on the class and even on the resources
available to the students, many different strategies will be used to assist them in their learning. However, since the school
currently has access to ClickView (a program very similar to – if not the same as –the learning objects used in this unit),
students are already familiar with the use of these types of computer activities. Therefore, it will be important to ensure that
all students are able to use computers and know how to follow links.
As a strategy to assist students to understand and analyse different types of multimodal scientific learning resources, it was
important to become quite familiar with the learning resources myself. To be able to lead students through the processes
confidently is of utmost importance.
Before looking at any of the learning objects, students will be told that they have been specifically developed for students just
like themselves. The learning objects are entirely original and students will be asked to critically analyse what they are
looking at while they complete the learning objects in order to critique the validity of the learning objects in terms of authentic
examples of current scientific understanding. Hopefully, they will notice the cool and hip characters (which are of course just
like themselves) that are used to put across important points and help the students to relate to the learning object better and
understand the link to their lives today.
Duration: 13 lessons (each lesson 45 minutes – except for two to three 90-minute lessons)
Implementation
Context for learning
Exploration: Students are able to move through a series of learning objects, increasing their understanding as they go.
There are paths off the main track that can take them to different levels of the topics, depending on how well they are
progressing through the work and learning objects (both skill- and time-wise).
Enquiry: Students will start with a question or topic and then complete smaller activities in order to consolidate ideas and
understanding.
Practice/Consolidation: Students have the very real option of working through the learning objects over and over again
until they have quite a high level of understanding. One of the great things about the learning objects is that they have
different levels within them that students can’t necessarily move on to until they have an understanding of the previous level.
Therefore, students consolidate their understanding without realising that they are learning more.
Application: One of the exciting aspects of this unit is that students have the chance to design and build a machine using all
or any of the types of simple machines learnt about in the unit. By incorporating hands-on activities, students definitely apply
their knowledge to a very real situation.
Assessment: Once the machine have been designed and built, students will have the opportunity to play with other designs
and, without even realising it (and because they are critical adolescents), they will be assessing the effectiveness of each
design. Students who are able to present their designs to the class will be able to complete self-assessment as well.
Lesson
Objectives
1
To determine what
students already know
about forces and to
start thinking about
forces
To introduce forces
(What are forces, force
arrows, contact and
non-contact forces?)
2
3
To investigate
balancing forces and
friction
4
To complete LA 5
5
To investigate simple
machines (particularly
mechanical
advantage, levers,
inclined planes and
wheel-and-axles)
6
To investigate pulleys
Year 7 - SIMPLE MACHINES
Instructions
1.
Start lesson giving students pre-test
(appendix 1)
2. Mark test as a class and discuss results
3. Split students into groups of 4 (max) to
complete introductory activity
1.
Ask students to think about the
introductory activity
2. “What do you think a force is?”
3. Discuss OHT 1 (students to copy into their
notebooks)
4. Complete Leaning Activity 1 (OHT 2)
5. Discuss OHT 3 (students to copy into their
notebooks)
6. Complete Learning Activity 2 (OHT 4)
7. Discuss OHT 5 (students to copy into their
notebooks)
8. Discuss OHT 6 (students to copy into their
notebooks)
9. Complete Learning Activity 3 (OHT 6,
Appendix 2)
1. Discuss OHT 7 (students to copy into their
notebooks)
2. Discuss OHT 8 (students to copy into their
notebooks)
3. Discuss OHT 9 (students to copy into their
notebooks)
4. Discuss OHT 10 (students copy into their
notebooks)
5. Complete Learning Activity 4 (OHT 10,
Appendix 3)
6. Complete Learning Activity 5 (OHT 10,
Appendix 4)
1. Students to complete LA 5
2. Students to complete practical report from
LA 5
1. Discuss OHT 11 (students copy into their
notebooks)
2. Discuss OHT 12 (students copy into their
notebooks)
3. Discuss OHT 13 (students copy into their
notebooks)
4. Discuss OHT 14 (students copy into their
notebooks)
5. Complete Learning Activity 6 (OHT 14,
Appendix 5)
6. Discuss OHT 15 (students copy into their
notebooks)
1. Discuss OHT 16 (students copy into their
notebooks)
2. Complete Learning Object LO1198 (also
completing 'Pulleys Worksheet' – appendix 6)
Learning Activities
(LA)
Resources/Materials
Class set of pre-test
Introductory activity
Introductory Activity
LA 1-3
Written practical report
OHT 1–6.
Learning
Activity
(Appendix 2)
LA 4 and 5
Written practical report
OHT 7–10
Learning
Activity
(appendix 3)
Learning Activity 5
(appendix 4)
LA 5
Learning Activity 5
(Appendix 4)
LA 6
OHT 11–14
Learning Activity 6
LA7 LO1198 (includes
1199, 1200 and 1201)
OHT 16
Class set of 'Pulleys
Worksheet' (Appendix 6)
Teacher
copy
of
worksheet
answers
3
4
7
To further investigate
pulleys
1. Briefly review last lesson
2. Complete Learning Activity 9 L4059–
L4063 (also completing 'Pulleys 2' Worksheet
– Appendix 8)
LA8 LO4059 – LO4063
8
To investigate gears
1. Discuss OHT 18 (students copy into their
notebooks)
2. Discuss OHT 19
3. Complete Learning Objects L481 (also
completing Wild Ride: in top gear worksheet
– Appendix 10)
LA 9 LO481
9
To assess students
and develop problem
solving and science
skills
LA10
Written report
10
Project
11
Project
12
Project
13
Test
1. Discuss OHT 20
2. Students to form groups of up to 5
students
3. Groups to work on Learning Activity 10
(designing their invention)
1. Working on their project
2. Writing their report
1. Working on their project
2. Writing their report
1. Presenting their project
2. Submitting their report
1. Student complete topic test
Learning resources
TLF learning objects:
Pulleys
TLF ID L1198
Acknowledgement – © Curriculum Corporation
This is an aggregated learning object combining three learning objects.
Pulleys: change the force
Pulleys: add more pulleys
Pulleys: lifting challenges
Pulleys
TLF ID L1199
TLF ID L1200
TLF ID L1201
TLF ID L1198
(Appendix 7)
Class
set/access
to
computers
OHT 17
Class set of Pulleys 2
Worksheet (Appendix 8)
Teacher copy of answers
(Appendix 9)
OHT 18-19
Class set of Wild Ride: in
top
gear
worksheet
(Appendix 10)
Teacher
copy
of
worksheet
answers
(Appendix 11)
OHT 20
Information re: LA10
(Appendix 12)
Appendix 13
Wild Ride: in top gear
TLF ID L481
Acknowledgement – © Curriculum Corporation
Other technologies
Equipment used in various experiments and in their final project design (varies from student to student depending on their
choice of project).
Learning products

Formal
Students will be expected to answer questions on worksheets accompanying learning objects as well as other questions
throughout the unit (as specified in the learning activities in the appendices). Students are also expected to complete various
practical reports on the activities that they do throughout the unit and then one on their final project. There are times where
peer learning takes place and therefore no formal assessment is provided.

Informal
At the start and end of each lesson teachers should assess knowledge and understanding from previous lessons by asking
questions directly to particular students or asking open ended questions to start discussions. Completing worksheets also
consolidates their understanding about the links between key concepts as well as providing a means of linking knowledge
gained from this unit with the wider topic.
Reflection
Teacher
Being the first time that this unit was taught, of course, it did not go as smoothly as I had wanted it to go, or I had imagined.
Of course, in the planning phase all students were perfect and responded very well to everything that was shown to them.
However, this did not take into account the storms we had, camps disrupting the unit, computer and internet failure or lessons
after lunch when the students were playing rather rough and energetic games where their last thoughts for the lesson would
be to settle down to a nice quiet theory lesson. Anyway, all in all, the unit went quite well. The students did think that the
learning objects were interesting and that the characters were pretty ‘cool’. They were able to relate well to them and even
have a bit of a laugh, which is always a bonus.
The students worked very well at the theory/textbook style lessons and whizzed through them all quickly, anticipating the
practical activities that were arranged. The students thoroughly enjoyed the practical activities and especially the learning
objects L481 Wild Ride: in top gear and L1198 Pulleys. If someone were to enter the classroom they would hear the excited
chatter of the students anticipating the correct gear in order to have the fastest time through the bike course or cheers as they
chose the fewest pulleys to lift the maximum load.
The main problem that was encountered was the inability to load the learning objects onto the main computer system.
Therefore, some students were unable to work on the learning objects until I had individually loaded the program onto each
laptop. Then, the next time we attempted to do it, it still didn’t work so I simply put the learning object onto the big screen at
the front of the classroom and we worked through it together as a class, which was not as terrible as I thought it would be.
Of course, next time will be a new class and without knowing the class really well, it is difficult to say what would be done
differently. However, I think that by separating the magnet unit a little more (perhaps having a bit of a topic test or some mini
assignment) would help smooth the unit slightly. However, having the magnets section in there added a little more interest
into their design for their machine invention.
For me, adding the digital content was both an advantage and a disadvantage. It was good because it made me use the
information technology equipment more, but that was also a bad thing as I had to be much organised and had to practise how
it all worked beforehand, so I didn’t look like a total novice to the students. When I couldn’t get the learning objects
downloaded I was a little stressed, but it all worked out in the end. Not perfectly, but that’s OK. For the students themselves,
who are very good at computers, being able to use them in the classroom for very specific learning was of huge benefit to
them.
Students
Students were asked what they thought about the learning objects that were used. The general response was that although
they were interesting, they were quite repetitive in what was being asked and often not advanced enough for the age group
that was indicated on the learning object.
Other resources:
Attached as appendices
OHT 1
FORCES IN
ACTION
What is a FORCE?
A FORCE is a push or a pull.
FORCES can







start a motion
stop a motion
speed up motion
slow down motion
change the direction of motion
change the shape of an object
have no visible effect at all
Now complete learning activity 1.
OHT 2
Learning Activity 1
Think, Pair, Share
1. Think about everything that you did last
weekend.
2. Think of five things that involved pulling
forces. (who/what was doing the pulling?)
3. Think of five things that involved pushing
forces. (who/what was doing the pushing?)
4. Give an example of something that is
caused by a force of gravity.
5. Give an example of a force lifting something.
6. Give an example of a force when something
bends.
7. Give an example of a magnetic force.
8. Give an example of an electrical force.
Now, share all your examples with the person
sitting next to you.
Now, share one of your examples with the rest
of the class.
OHT 3
FORCE ARROWS
DIRECTION of force
Forces
can
act
upwards,
downwards, sideways or any
direction at all.
To show the direction of a force
you can use an arrow drawn from
the centre of the object.
STRENGTH of force
You can then show the strength
of a force by the length of the
arrow.
OHT 4
Learning Activity 2
Consider the following situations
and then draw a diagram to depict
direction and strength of the force:
1. A batsman gently taps the
cricket ball so it lands about 2m in
front of him.
2. The batsman then whacks the
cricket ball for six runs way out to
the left of him.
3. The batsman now hits the ball
to his right just hard enough to
make two runs.
OHT 5
TYPES OF FORCES
As you have seen in learning
activities 1 and 2, there are many
different types of forces.
Some forces act by contact and
are therefore called contact
forces.
Examples of contact forces are:
 pushing a wheelbarrow
 pulling on a rope
 wind blowing the trees
 waves crashing on the shore
What other contact forces can you
think of?
OHT 6
Some forces do not need contact
with anything. These are called noncontact forces.
Examples of non-contact forces are:
 magnetic forces
 gravity
 electrical forces
Now, in groups of 3–4, complete
Learning Activity 3.
Learning Activity 3
Complete the practical activity
“Magnetic forces are non-contact
forces” and write up a practical
report to discuss your results.
OHT 7
Balanced and Unbalanced Forces
When forces are balanced there is
no change in an object’s motion.
For example, in a game of tug-ofwar, when two equally strong teams
are pulling in opposite directions the
central rope marker does not move.
Also, if you balance 100g on one end
of a scale and 100g on the other end
of the scale, the scale is perfectly
horizontal and balanced.
What other examples can you think
of? Share them with the person next
to you.
Now, share them with the class.
OHT 8
When forces are unbalanced there
is a change in motion.
Use the two examples above to
describe how to make them
unbalanced.
In a game of tug-of-war, when two
equal forces are pulling in opposite
directions the central rope marker
does not move.
However, when one of those forces
is bigger (such as adding an extra
person to one side of the rope), the
rope can be pulled to one side, and
the side with more people will win.
How would you then make this tugof-war game balanced again?
OHT 9
Measuring Forces
A spring stretches when a
pulling forces acts on it and is
squashed or compressed when
a pushing forces acts on it.
The bigger the force, the more it is
stretched or compressed.
Therefore, a spring can be used to
measure the strength of a force.
The unit used to measure force is
called the Newton (N), named
after Sir Isaac Newton.
However, friction can have an
effect on the strength of a force.
OHT 10
Friction
Friction is the force acting on an
object when it moves against the
surface of another object.
Friction acts when the two surfaces
touch.
Learning Activity 4
Complete the practical activity
“Learning about Friction” and answer
the discussion questions to discuss
your results.
Learning Activity 5
Complete the practical activity
“Investigating Friction” and write up
your results as a practical report.
OHT 11
SIMPLE MACHINES
Everyone uses simple machines
everyday.
Some common examples are:
 levers
 pulleys
 inclined planes (ramps)
 screws
 gears
Machines help make jobs easier in
three different ways:
1. Magnify the force used
2. Change the direction of a force
3. Make things go faster
What are some more examples?
OHT 12
Levers
Suppose you are late for a party,
but there is a big rock blocking the
door so you can’t get your bike
out. How would you move it?
Look at the picture below and
copy it down.
Pivot (small rock)
Effort
Crowbar
Big rock (load)
Describe how this would work.
OHT 13
A lever moves around a pivot,
which is a fixed point. In the
picture above, the pivot (also
called the fulcrum) is the smaller
rock. The force you apply is called
the effort.
When you apply force on the
crowbar you are using much less
force than you would if you were
to move the rock yourself.
Therefore, the crowbar has a
force advantage because you
use less force.
OHT 14
The usefulness of a simple machine
is measured by its mechanical
advantage, which is the force of the
load divided by the effort required to
move it.
For example, if you apply a force of
100N to move a 500N rock, this is
how you would work it out:
Mechanical Advantage = load
effort
= 500N
100N
=5
Learning Activity 6
Complete the practical activity “Using
Levers” and answer the discussion
question to discuss your results.
OHT 15
SIMPLE MACHINES
Inclined
planes
work
by
increasing the distance covered
but decreasing the effort needed
to move that distance.
For example, ramps, screws, axes
and car jacks are all inclined
planes. Discuss why.
Wheel-and-axles are like a
steering wheel, screwdrivers or a
door knob. How do you think
these work as simple machine?
OHT 16
PULLEYS
Pulleys work in very special ways.
By pulling downwards the load is
lifted upwards.
Learning Activity 7
Work through the Learning Object
1198 “Pulleys” and complete the
accompanying worksheet (due at
the end of the lesson).
OHT 17
Learning Activity 8
Work through the Learning
Objects L4059–L4063 “Pulleys 2”
and complete the accompanying
worksheet (due at the end of the
lesson).
OHT 18
GEARS
Gears are wheels that have small
teeth on them. The teeth on one
gear fit perfectly between two
teeth on another gear.
Gears are used to transfer the
force from one gear to another.
On a bike, the larger gear
attached to the pedals is called the
driving gear.
Gears can do three things:
1. Speed things up
2. Slow things down
3.
Change the direction of the
force.
OHT 19
Learning Activity 9
Work through the Learning
Objects L481 “Wild ride: in top
gear”
and
complete
the
accompanying worksheet (due at
the end of the lesson).
OHT 20
Learning Activity 10
In small groups (up to 5 people),
you are to invent a device that will
complete one of the following:
1. Raise a weight, move it 50 cm
then lower it.
2. Pull a block of wood over the
surface of a table.
3. Any other design that involves
at least three different types of
simple machines.
Step 1:
Step 2:
Step 3:
Step 4:
Step 5:
Choose your project
Design your device
Check with your teacher
Collect all equipment
Build it and test it!
APPENDIX 2
MAGENTIC FORCES ARE NON-CONTACT FORCES
Learning Activity 3
Aim: to demonstrate that magnets use force without making contact.
Materials: (for a class of 30 – split class into groups of 5)
6 Magnets
6 Paper clips
6 containers of Iron filings
6 pieces of Paper
6 pieces of String
Sticky-tape/plasticine
6 Retort stands
6 sets of Boss head and clamp
Sheets of various materials (paper, glass, plastic, tin, iron, wood, aluminium, etc)
Method 1:
Step 1: Set up the equipment as shown below:
Magnet
Sheet of material
Boss head and clamp
paper clip
Retort stand
string
Plasticine/tape
Be sure to have the string long enough so that you can slip one of the sheets of
material between the paper clip and the magnet.
Step 2: Place each different sheet of material between the paperclip and the
magnet.
Step 3: Complete the table below:
Material
Did the paper clip fall?
Method 2:
Step 1: Set up the equipment as shown below:
Book 1
Piece of paper
Magnet
Book 2
Step 2: Gently sprinkle the iron filings onto the sheet of paper above the magnet.
Step 3: Draw a diagram of the pattern made by the iron filings.
Step 4: Carefully, move the magnet around under the paper to see what
happens to the iron filing pattern.
Discussion:
1. Consider the paperclip attached to the string, but not quite touching the
magnet. What are the forces acting on the paperclip?
2. What do you think would happen if you suddenly cut the string?
3. What generalisation can you come up with about the types of materials that
attract the paperclip?
4. How do you think that the pattern from the iron filings was formed?
5. What happened when the magnet was moved under the iron filings?
6. What evidence can you give from method one to support the fact that
magnetic forces are non-contact forces?
APPENDIX 3
LEARNING ABOUT FRICTION
Learning Activity 4
Aim: to measure the force of friction between different surfaces.
Materials: (for a class of 30 – split class into groups of 5)
6 Blocks of wood with a hook in one end
6 Spring balances
Various surfaces (carpet, brick, concrete, linoleum, tiles, grass, etc)
Method:
Step 1: Set up the equipment as shown below:
Direction of pull
Block of wood
Hook
Spring balance
Surface
Step 2: Hook the spring balance onto the hook on the wood.
Step 3: Pull the spring balance so that the block of wood moves at a constant
speed over the surface.
Step 4: Record the force required to pull the block of wood three times and then
calculate an average for that surface (see table below).
Surface
type
Force required to pull block of wood (Newtons)
Prediction
Attempt 1
Attempt 2
Attempt 3
Average
Discussion:
1. Why was it important to test each surface three times and then calculate an
average?
2. Draw a graph to show your results.
3. Which surface produced the most amount of friction? Why is this?
4. Which surface produced the least amount of friction? Why is this?
APPENDIX 4
INVESTIGATING FRICTION
Learning Activity 5
Aim: To investigate one of the following questions:
(A)
How can frictional force be reduced?
(B)
What happens to frictional force if you increase the mass of the object?
(C)
How does the area of contact between the block and the surface affect
the frictional force?
Materials: (for a class of 30 – split class into groups of 5)
6 Blocks of wood with a hook in one end
6 Spring balances
Various surfaces (carpet, brick, concrete, linoleum, tiles, grass etc)
Different weights
Method:
Step 1: Each group needs to decide on which investigation to complete from the
three listed in the aim.
Step 2: Each group then needs to design an investigation that will answer their
question.
Step 3: Each student in each group must write a practical report discussing their
results.
APPENDIX 5
USING LEVERS
Learning Activity 6
Aim: to investigate different types of levers.
Materials: (for a class of 30 – split into groups of 5)
6 metre-long rulers
Different brass masses
12 hangers
18 large paper clips (bent to form an S)
6 spring balances
6 retort stands
6 sets of boss head and clamp
Method:
Step 1: set up equipment as shown below.
Ruler
25cm mark
Boss head and clamp
paper clips holding
masses on hangers
Retort stand
Step 2: Attach metre ruler using another ‘S’ shaped paper clip to the boss head
and clamp at the 25cm mark.
Step 3: Add 100g to one end of the ruler
Step 4: Find the effort needed to balance the ruler by adding masses to the
other end of the ruler.
Step 5: Repeat for 150g, 200g and 250g
Step 6: Record results in the following table:
Load (mass in g)
Force produced
by the load
Effort (N)
Mechanical
Advantage
100g
150g
200g
250g
Note: to calculate Force, divide mass by 100).
Step 7: Investigate the effect if you move the position of the pivot from 25cm to
other positions.
Discussion:
1. Write a generalisation about the position of the pivot, load and effort.
APPENDIX 6
Pulleys
Work your way through the Pulleys learning object and answer the following questions.
All the questions should be in the correct order as you work your way through.
1. What is a pulley? _______________________________________________________
________________________________________________________________________
2. What is mass measured in? _______________________________________________
3. What is the distance that the rope is pulled to lift an object measured in? ___________
4. What measurement is used for force? _______________________________________
5. Who was the Newton named after? ________________________________________
6. What is a Newton?
________________________________________________________________________
7. Complete this sentence: The work needed to lift a load is equal to ________________
________________________________________________________________________
Use Activity One (Change the Force) to complete questions 8 and 9.
8. Fill out the table below:
Number of
pulleys
Crate mass
(kg)
Force applied
by workers
(N)
Distance rope
is pulled
(m)
Work done
(force χ
distance)
9. What were the three correct statements?
(i)
____________________________________________________________
____________________________________________________________
____________________________________________________________
(ii)
____________________________________________________________
____________________________________________________________
____________________________________________________________
(iii)
____________________________________________________________
____________________________________________________________
____________________________________________________________
Use Activity Two (Add more pulleys) to complete questions 10 and 11.
10. Fill out the table below:
Number of
pulleys
Crate mass
(kg)
Force applied
by workers
(N)
Distance rope
is pulled
(m)
Work done
(force χ
distance)
11. What were the three correct statements?
(i)
____________________________________________________________
____________________________________________________________
____________________________________________________________
(ii)
____________________________________________________________
____________________________________________________________
____________________________________________________________
(iii)
____________________________________________________________
____________________________________________________________
____________________________________________________________
12. Draw a diagram that shows one worker lifting a 100kg box (be sure to show the
correct number of pulleys).
13. Write a concluding statement that relates pulleys to force. _____________________
________________________________________________________________________
________________________________________________________________________
APPENDIX 7
Pulleys
(Answers)
Work your way through the Pulleys Learning Object and answer the following questions.
All the questions should be in the correct order as you work your way through.
1. What is a pulley? A wheel that changes the direction of a force applied with a rope.
2. What is mass measured in? Kilogram
3. What is the distance that the rope is pulled to lift an object measured in? Metre
4. What measurement is used for force? Newton
5. Who was the Newton named after? Sir Isaac Newton
6. What is a Newton? The force needed to accelerate a 1kg object at a rate of 1 metre
per second, every second
7. Complete this sentence: the work needed to lift a load is equal to the distance the
rope is pulled multiplied by the force
Use Activity One (Change the Force) to complete questions 8 and 9.
8. Fill out the table below: answers depend on the problems given to the students
Number of
pulleys
Crate mass
(kg)
Force applied
by workers
(Newtons)
Distance rope
is pulled
(m)
Work done
(force χ
distance)
9. What were the three correct statement?
(i)
work equals force multiplied by the distance_______________________
____________________________________________________________
____________________________________________________________
(iv)
work equals the mass of the object ______________________________
____________________________________________________________
____________________________________________________________
(v)
pulleys reverse the direction of the force__________________________
____________________________________________________________
____________________________________________________________
Use Activity Two (Add more pulleys) to complete questions 10 and 11.
10. Fill out the table below: answers will depend on the problems given to the students
Number of
pulleys
Crate mass
(kg)
Force applied
by workers
(Newtons)
Distance rope
is pulled
(m)
Work done
(force χ
distance)
11. What were the three correct statements?
(iv)
It’s easier to lift things with 2 pulleys than with 1 ___________________
____________________________________________________________
____________________________________________________________
(v)
The more pulleys you use, the less the force you need to apply_________
____________________________________________________________
____________________________________________________________
(vi)
With 3 pulleys, you need to pull more rope than with 2 pulleys_________
____________________________________________________________
____________________________________________________________
12. Draw a diagram that shows one worker lifting a 100kg box (be sure to show the
correct number of pulleys).
With 4 pulleys, there will
be 4 times as much rope
pulled as the object will
be lifted. For example, if
the object is lifted 1m,
then 4m of rope needs to
be pulled.
13. Write a concluding statement that relates pulleys to force. By adding more pulleys,
you don’t need to use as much force to lift an object. Also, by adding more pulleys, one
person can lift more mass.
APPENDIX 8
PULLEYS 2
Questions 1–4 from L4059
1. Complete the following table based on your results:
Mass (kg)
Force (N)
10
15
20
25
2. Now construct a line graph based on the results above:
3. What is the link between the weight of the crate and the force required to lift it
________________________________________________________________
________________________________________________________________
4. Complete this sentence: If there is one pulley, the minimum force needed to
lift a crate is ______________________________________________________
Question 5–8 from L4060
5. Complete the following table based on your results:
Mass (kg)
Force (N)
2 pulleys
Force (N)
3 pulleys
Force (N)
4 pulleys
12
24
36
48
6. Now construct a line graph based on the results above:
7. What is the link between the weight of the crate and the force required to lift it
________________________________________________________________
________________________________________________________________
8. How much force is needed to lift a crate that has a mass of 115kg with 5
pulleys attached? _________________________________________________
Questions 9-13 from learning object L4061
9. Complete the following table based on your results:
Number of
pulleys
Force (N)
1
2
3
10. Now construct a line graph based on the results above:
4
11. The graph illustrates the force needed to lift 24kg using different number of
pulleys. Does it make sense to join the dots? Explain.
________________________________________________________________
________________________________________________________________
________________________________________________________________
12. What type of graph should you use for this information?
________________________________________________________________
13. What is the link between the number of pulleys and the force required to lift
________________________________________________________________
________________________________________________________________
Questions 14-17 from learning object L4062
14. Complete the following table based on your results:
Number of
pulleys
Length of rope
(m)
1
2
3
4
15. Now construct a line graph based on the results above:
16. What is the link between the number of pulleys and length of rope pulled?
________________________________________________________________
________________________________________________________________
17. If you used six pulleys and 10N to lift a crate weighing 60kg, how far would
the rope move? __________________________________________________
Now, complete learning object L4063
Questions 18 – 19 are general questions
18. How far would the rope move if a 123kg object used 4 pulleys and a force of
13N to lift it? ______________________________________________________
19. Circle the correct statements from the choices below:
(a)
the distance the rope moves is equal to the number of pulleys
(b)
the distance the rope moves is equal to the force multiplied by the
number of pulleys
(c)
the distance the rope moves is equal to the mass divided by the
number of pulleys
APPENDIX 9
PULLEYS 2
(ANSWERS)
Questions 1–4 from L4059
1. Complete the following table based on your results:
Mass (kg)
Force (N)
1.
10
10
15
15
20
20
25
25
Now construct a line graph based on the results above:
3. What is the link between the weight of the crate and the force required to lift it
The weight of the load is equal to the force required to lift it
4. Complete this sentence: if there is one pulley, the minimum force needed to
lift a crate is equal to the mass of the crate
Question 5–8 from L4060
5. Complete the following table based on your results:
Mass (kg)
Force (N)
2 pulleys
Force (N)
3 pulleys
Force (N)
4 pulleys
12
6
24
12
36
18
48
24
4
8
12
16
3
6
9
12
6. Now construct a line graph based on the results above:
7. What is the link between the weight of the crate, the number of pulleys and
the force required to lift it?
The force required to lift a load is equal to the mass of the load. As the number
of pulleys increases, the force required to lift the load decreases, regardless of
mass of the load.
8. How much force is needed to lift a crate that has a mass of 115kg with 5
pulleys attached? 11.5N
Questions 9-13 from learning object L4061
9. Complete the following table based on your results:
Number of
pulleys
Force (N)
1
2
3
4
24
12
6
3
10. Now construct a line graph based on the results above:
11. The graph illustrates the force needed to lift 24kg using different number of
pulleys. Does it make sense to join the dots? Explain.
Cannot join the dots as you cannot have fractions of a pulley.
12. What type of graph should you use for this information?
Bar graph
13. What is the link between the number of pulleys and the force required to lift
As the number of pulleys increases, the force required to lift the load decreases.
Questions 14–17 from learning object L4062
14. Complete the following table based on your results:
Number of
pulleys
Length of rope
(m)
1
2
3
4
1
2
3
4
15. Now construct a line graph based on the results above:
16. What is the link between the number of pulleys and length of rope pulled?
As the number of pulleys increases, the length of rope increases.
17. If you used six pulleys and 10N to lift a crate weighing 60kg, how far would
the rope move? 6m
Now, complete learning object L4063
Questions 18–19 are general questions
18. How far would the rope move if a 123kg object used 4 pulleys and a force of
13N to lift it? 4m
19. Circle the correct statements from the choices below:
(d)
the distance the rope moves is equal to the number of pulleys
(e)
the distance the rope moves is equal to the force multiplied by the
number of pulleys
(f)
the distance the rope moves is equal to the mass divided by the
number of pulleys
APPENDIX 10
Wild Ride: in top gear
Work your way through L481 Wild ride: in top gear learning object and answer the
following questions. All the questions should be in the correct order as you work your
way through.
1. What are gears? ________________________________________________________
________________________________________________________________________
2. Why was the ability to change gears a major advantage in cycling? _______________
________________________________________________________________________
3. When and who invented the Derailleur gear system? ___________________________
________________________________________________________________________
4. Briefly describe how the Derailleur gear system worked? ______________________
________________________________________________________________________
5. When and who invented the first modern cable-operated derailleur? ______________
________________________________________________________________________
6. How does the derailleur change the pedalling speed? __________________________
________________________________________________________________________
7. What is a ‘crank set’? ____________________________________________________
________________________________________________________________________
8. How many crank sets does a chain wheel usually have? _________________________
________________________________________________________________________
9. How do you calculate the number of gears that a bike has? ______________________
10. In the example, how many cogs are there? __________________________________
11. How many gear rings are the? ____________________________________________
12. Therefore, how many gears are there? _____________________________________
13. After you have completed the activity to see at which cadence Zak was most
comfortable, what was the result? ____________________________________________
14. What does cadence mean? ______________________________________________
________________________________________________________________________
15. What is cadence measured in? ___________________________________________
16. What effect could pedalling too slow have on your body? ______________________
________________________________________________________________________
17. When would a cyclist use a lower than normal cadence? ______________________
________________________________________________________________________
18. Thinking about the test Zak did on the exercise bike in the caravan, why do you think
that this did not really reflect what it is like when you are cycling outside? ____________
________________________________________________________________________
19. What affect will an adjustment to the ‘load’ control have on the chainwheel and Zak?
________________________________________________________________________
________________________________________________________________________
20. What would be the preferred pedalling range for a beginner cyclist? _____________
21. What would be the preferred pedalling range for a top cyclist? __________________
22. How would you create more power when pedalling? __________________________
________________________________________________________________________
23. But, what effect does this have on your body? _______________________________
24. What would happen if you pedalled too fast? ________________________________
25. When and why would a professional cyclist exceed a cadence of 100rpm? ________
________________________________________________________________________
Use the next activity to answer questions 26–28.
26. You’re riding down hill and your cadence becomes too fast. What cog and gear
would you use? __________________________________________________________
27. You climb onto the bike and start pedalling, but it is really hard to turn the pedals.
What cog and gear choice would you use? _____________________________________
28. You’re pedalling in your preferred cadence range, but you want a quick burst of
speed to get to the finish line. Which gear would you use? ________________________
Use the next activity to answer questions 29–31.
29. What does it mean when the cadence graph is above the green zone? ____________
________________________________________________________________________
30. What gear should you be in when the cadence graph is above the green zone? ______
31. Run the BikeSim tests again and concentrate on the picture of the bike and the
correct gear choices. Answer the following questions:
(a)
When the bike is on the flat, what was the best gear choice? ___________
(b)
When the bike was going uphill, what was the best gear choice? _______
(c)
When the bike was doing downhill, what was the best gear choice? _____
Use the next activity to answer questions 32–35.
32. What was your best time on the BikeSim track for track 1? ____________________
33. What was your best time on the BikeSim track for track 2? ____________________
34. What was your best time on the BikeSim track for track 3? ____________________
35. What was your best time on the BikeSim track for track 4? ____________________
APPENDIX 11
Wild Ride: in top gear
(ANSWERS)
Work your way through the Wild Ride: in top gear Learning Object and answer the
following questions. All the questions should be in the correct order as you work your
way through.
1. What are gears? Gears are a set of toothed wheels (cogs) of different sizes that allow a
cyclist to change their pedalling speed
2. Why was the ability to change gears a major advantage in cycling? It allowed the
rider to pedal at a more consistent rate (known as cadence) whether going uphill,
downhill or along a flat surface.
3. When and who invented the Derailleur gear system? 1905 by Paul de Vivie
4. Briefly describe how the Derailleur gear system worked? It uses a system of rods to
derail the chain onto different gears (moving it from one cog to another).
5. When and who invented the first modern cable-operated derailleur? Tullio
Campangnolo in the 1950s.
6. How does the derailleur change the pedalling speed? The rider moves a lever, pulling
a wire that moves a jockey wheel on the derailleur from side to side, transferring the
chain onto a different cog.
7. What is a ‘crank set’? A crank set consists of a front sprocket and two cranks. Pedals
attach to the cranks. The front sprocket is also called a chain wheel.
8. How many gear rings does a chain wheel usually have? Between 1 and 4.
9. How do you calculate the number of gears that a bike has? Multiply the number of
cogs by the number of gear rings on the crank set.
10. In the example, how many cogs are there? 9
11. How many gear rings are the? 3
12. Therefore, how many gears are there? 27
13. After you have completed the activity to see at which cadence Zak was most
comfortable, what was the result? 75rpm
14. What does cadence mean? pedalling speed
15. What is cadence measured in? rpm (revolutions pre minute)
16. What effect could pedalling too slow have on your body? wastes energy and
increases the risk of muscle strain
17. When would a cyclist use a lower than normal cadence? going up steep
hills
18. Thinking about the test Zak did on the exercise bike in the caravan, why do you think
that this did not really reflect what it is like when you are cycling outside? he doesn’t
have to overcome wind resistance or the effects of track surface
19. What would be the preferred pedalling range for a beginner cyclist? 30-80rpm
20. What would be the preferred pedalling range for a top cyclist? 80-100rpm
21. How would you create more power when pedalling? by pedalling faster
22. But, what effect does this have on your body? more and more energy gets used up
23. What would happen if you pedalled too fast? you will get tired very quickly
24. When and why would a professional cyclist exceed a cadence of 100rpm? when
they sprint to the finish
Use the next activity to answer questions 25– 27.
25. You’re riding down hill and your cadence becomes too fast. What cog and gear
would you use? smaller cog, middle gear
26. You climb onto the bike and start pedalling, but it is really hard to turn the pedals.
What cog and gear choice would you use? larger cog, middle gear
27. You’re pedalling in your preferred cadence range, but you want a quick burst of
speed to get to the finish line. Which gear would you use? low
Use the next activity to answer questions 28–30.
28. What does it mean when the cadence graph is above the green zone? you’re
pedalling too fast
29. What gear should you be in when the cadence graph is above the green zone?
higher gear
30. Run the BikeSim tests again and concentrate on the picture of the bike and the
correct gear choices. Answer the following questions:
(d)
When the bike is on the flat, what was the best gear choice? middle
(e)
When the bike was going uphill, what was the best gear choice? low
(f)
When the bike was doing downhill, what was the best gear choice? high
Use the next activity to answer questions 31-34.
31. What was your best time on the BikeSim track for track 1? ____________________
32. What was your best time on the BikeSim track for track 2? ____________________
33. What was your best time on the BikeSim track for track 3? ____________________
34. What was your best time on the BikeSim track for track 4? ____________________
APPENDIX 12
Small Group Invention
Students are expected to work in small groups to invent a useful device
containing simple machines such as levers, gears and pulleys.
Planning:
Step 1: Decide what invention you will design
Step 2: Show your design to you teacher for approval to use specific resources
Construction:
Step 3: Collect all the resources that you will need (some of them might be
available from your scientific technician)
Step 4: Build your design and test it.
Conclusion:
Step 5: Write a report explaining the following:
1.
Describe your invention (include a drawing or photograph of your design)
2.
How did you come up with the idea (why is it useful?)
3.
What simple machines did you use and how do they all work together?
4.
What did you do to make your design even better after you tested it for the
first time?
5.
What could you do to your design to make it even better if you had
unlimited resources?
APPENDIX 13
GRADE 7 SCIENCE
FORCES, SIMPLE MACHINES AND
MAGNETS
TEST
Name: ___________________________________________
FORCE:
1. Give a definition of force _____________________________________________
_____________________________________________________________________
(1 mark)
2. Name three things that a force can do to an object
_________________________________
_________________________________
_________________________________
(3 marks)
3. Give an example of a contact force ______________________________________
(1 mark)
4. Give an example of a non-contact force __________________________________
(1 mark)
5. Circle true or false in the following examples:
(a)
force
A tug-of-war between three 8-year-olds and three 30-year-olds shows a balanced
True
/ False
(b) A car travelling at a constant speed demonstrates a balanced force
True
/ False
(2 marks)
6. What is force measured in? ____________________________________________
(1 mark)
7. Explain one situation when friction is a good thing _________________________
_____________________________________________________________________
(1 mark)
8. Explain one situation when friction is a bad thing __________________________
_____________________________________________________________________
(1 mark)
9. Name two ways that friction can be reduced ______________________________
____________________________________________________________________
(2 marks)
(Total:
/13)
SIMPLE MACHINES:
10. Simple machines help you do things more easily. They do this in three ways.
Describe two of them:
_____________________________________________________________________
_____________________________________________________________________
_____________________________________________________________________
11. Complete this table:
(2 marks)
Load (N)
Effort (N)
500
100
Mechanical Advantage
50
10
5
25
(3 marks)
12. Connect the examples in Column A to their type of simple machine in Column B.
Column A
Column B
Screw
Screwdriver
Wheelbarrow
Wheel-and-axle
Inclined plane
Lever
(3 marks)
13. Explain how a pulley system works in terms of amount of force used and mass you
can lift.
_____________________________________________________________________
_____________________________________________________________________
14. When you are riding a bike, what gear should you be in when you are:
(2 marks)
(a) just pushing off
_____________________________________________
(b) going up hill
_____________________________________________
(2 marks)
(Total:
MAGNETS:
15. Decide whether the following magnets will repel or attract each other.
(a)
(b)
(c)
N
S
N
S
__________________
N
S
S
N
__________________
N
S
(d)
N
S
__________________
N
S
__________________
N
S
__________________
S
N
N
__________________
/12)
(6 marks)
16. Draw a picture to show three magnets arranged in a triangle so that each magnet
is attracted to the one next to it.
(2 marks)
17. Magnetic fields are non-contact forces. What does this mean?
_____________________________________________________________________
_____________________________________________________________________
_____________________________________________________________________
(1 mark)
18. Use the magnets below to show where the magnetic forces would be if you
sprinkled iron filings onto a piece of paper and lowered the paper onto the magnet.
N
S
(2 marks)
19. Describe what magnetic shielding is.
_____________________________________________________________________
_____________________________________________________________________
_____________________________________________________________________
(1 mark)
20. Name two ways that the strength of an electromagnet can be increased.
(a)
________________________________________
(b)
________________________________________
(Total:
(2 marks)
/14)