Forces and Simple Machines
Learning Area:
Science
Year Level: Y7
Duration
4 – 6 weeks (approx. 18 lessons)
Content
This unit is designed to introduce students to the idea of a force as a push, a pull or a twist and that forces act
in pairs. Students will build an understanding and knowledge of the way things move and the sorts of forces
that act to produces those movements, for example that a force is a push or a pull and the change in an
object’s motion is caused by unbalanced forces acting on the object. They will explore magnetic and
electrostatic forces, the forces exerted on the earth by the moon to cause tides and how forces are put to use
in simple machines. They will understand that gravity is a force which pulls objects towards the centre of the
Earth.
This will be extended into a short course of practical application in robotics. In this unit is about Robotics –
The Construction, Programming and Applications of Robotics. Students will be given an introduction to the
use of the LEGO Mindstorm NXT kits & how they are programmed. Students will work in small groups (2 or 3)
through self directed construction and programming exercises using the LEGO Mindstorms NXT kits. This may
be followed [if time permits] by a series of Challenge activities that will involve developing and implementing
a range of tasks and skills (That build on those learnt through Robot Educator). These challenges are designed
to allow for success at many different levels. A number of these challenges are deliberately open ended to
encourage creative design and problem solving
Key Terms: Actuator, applied force, axle, balanced force, contact force, effort, electrostatic, energy,
ergonomic, force, friction, fulcrum, gear, gear ratio, gravitational force, gravity, gripper, inclined
plane, joule, kinetic energy, level, lever, load, machine, magnet, magnetic force, multiplier, noncontact force, pivot, potential energy, power, pulley, ratio, robot, sensor, simple machine, simple
machines, speed, tide, torque, total (net) force, unbalanced force, weight, wheel and axle, work.
Force, motion, non-contact, unbalanced, non-magnetic, field, electromagnet, charges, mass, weight,
resistance, surface tension, buoyancy.
Aims and Objectives
SKILLS:
Upon completion of this unit, students will be able to...
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Describe a force as a push, pull or twist.
represent the forces acting on an object in a diagram
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recognise situations in which the forces acting on an object balance each
other out
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describe friction as a force that opposes motion
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identify and describe the changes in motion caused by forces
investigate the effects of applying different forces to familiar objects
investigate common situations where forces are balanced, such as stationary
objects, and unbalanced, such as falling objects
List the five types of simple machine
Describe how a simple machine can reduce the amount of effort needed for a
task
investigate a simple machine such as lever, ramp or pulley system
explore how gravity affects objects on the surface of Earth
consider how gravity keeps planets in orbit around the sun
Describe how a robot can be programmed
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Describe the process of inquiry and use appropriate techniques for posing
questions, defining problems, processing and evaluating data, drawing
conclusions and flexibly applying findings to further learning and to creating
new solutions
KNOWLEDGE:
Upon completion of this unit, students will know...
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That a force is a push, a pull or a twist & are either contact or non-contact
That forces act in pairs
That force cannot be seen
Change to an object’s motion is caused by unbalanced forces acting on the object
That a machine is a tool which makes a task easier to do
The difference between a load force and an effort force
That a simple machine is one of five basic types of machine from which all other
machines are made.
That a robot is essentially made up of five basic components of:
1. A movable physical structure
2. Some sort of motor
3. A sensor system
4. A power supply
5. A computer “brain” that controls all of these elements All matter is made of particles
The basic unit of energy is the Joule
That ‘energy’ is the ability of something to do work, that energy can neither be created
nor destroyed but is transferred or transformed from one form into other forms
UNDERSTANDING:
Upon completion of this unit, students will know...
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That forces enable many of the things which we do in daily life to happen
That simple machines make many tasks easier to do
Earth’s gravity is a force which pulls objects towards the centre of the Earth
how robots work and are constructed.
why we use robots and the many different fields and uses that robots have (and will
have) in society.
the need for space and measurement in the design and use of robots.
the practical applications of mathematics such as number and fractions in programming
robots.
how to develop and produce appropriate structural engineering solutions using
problem-solving strategies.
how to develop and produce appropriate computer programming solutions using
problem-solving strategies to solve challenges.
the place of robots in our society, their social impacts and the features of a future world
containing robots.
Resources
 Nelson Science 7
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https://fuse.education.vic.gov.au/?XRK9RB
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Boardworks PowerPoint: 7K Forces and their Effects
http://www.bbc.co.uk/schools/ks3bitesize/science/energy_electricity_forces/forces/activity.shtml
Good explanation of Gravity, Forces and the measurement of forces.
http://classroom.jc-schools.net/sci-units/force.htm#8
http://www.fi.edu/qa97/spotlight3/spotlight3.html
http://sunshine.chpc.utah.edu/javalabs/java12/machine/stdntovrvw.htm
http://www.tryengineering.org/lessons/trebuchettoss.pdf
http://www.amazingscienceonline.com/mechanics Try the Extreme Challenge!
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Most of the materials for the robotics part of the unit are found at the Yr 7 Science Wiki & the # New S
Drive Science [somewhere]:
http://scienceklawantirnacollege2012.wikispaces.com/Year+7+Core+Science:
 http://www.robotassemblies.com/resources.htm great intro to robotics in schools
 http://www.mdc.net/~rmaynard/html/brainstorm.htm
 http://ldaps.ivv.nasa.gov/Curriculum/legoengineering.html
 http://www.rcn.com/dc-metro/
 http://british.nerp.net/lego/index.html
 http://www.cs ruu.nl/people/markov/lego/index.html
 http://mindstorms.lego.com/en-us/default.aspx?domainredir=www.legomindstorms.com
 http://www.nxtprograms.com/projects.html
 http://www.rhino3d.com/download.htm
 http://www.tainlab.com.au
 http://www.robotics.com.au
 http://www.enteract.com/~dbaum/lego/
 http://www.legomindstorms.com
 http://www.youtube.com/watch?v=b2bExqhhWRI&feature=fvst robot big dog
 http://www.youtube.com/watch?v=EzjkBwZtxp4 robot violinist
 http://www.youtube.com/watch?v=W1czBcnX1Ww big dog new video
 http://www.robotclips.com/ robot clips
 http://www.youtube.com/watch?v=W3f6BOrD9Ek&feature=channel robot of the year award
 http://www.abc.net.au/catalyst/stories/2856325.htm future car
 http://www.youtube.com/watch?v=aQS2zxmrrrA expression
 http://www.youtube.com/watch?v=rSKRgasUEko NAO
 http://www.youtube.com/watch?v=lWsMdN7HMuA&NR=1&feature=fvwp warehouse robots at
work
 http://www.youtube.com/watch?v=7FD2bQMMwV0&feature=related Japanese android
Activities, Products and Assessment
Learning Activities:
Student Products
Assessment
What are forces?
 Notes from Boardworks PPt
Forces
 P136-147 Sc Alive 1
 Differentiate between forces
as contact & non-contact,
action/reaction pairs, pull,
push or twist, balanced or
unbalanced
 “Describing Forces” Nelson 7
 Questions from Nelson 7
 Modelling Tides experiment
Activity 10.12 Nelson 7
 Classroom discussion
 Completed set of notes and
skill work
 Formative assessment
Practical reports
 Formative assessment
Measuring Forces Prac
CAI Task P141
 Balloon Rockets
experiment
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Develop an understanding of the
application of forces to simple
machines:
 Edheads site, “See a Need”
worksheet
 Inclined Plane experiment
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Develop an understanding of
forces with regard to simple
machines:
 Save an Egg Experiment
10.6 Nelson 7Measuring
Forces Prac
 Designing Parachutes P147
Sc Alive 1
Develop an understanding of
the application of simple
machines to robots.
 Complete the building
basic robot [sumo] &
programming of the basic
robot
Analyse and create a program
for a robot to complete a
simple task
 Completion programming
of the “Driving Course”
exercise;
 participation in a robot
race/challenge
 Edheads Worksheets
 Inclined Plane Practical
reports
 “Save an Egg” & Parachute
Practical reports
 Complete the “Driving
course” challenge
 Rube Goldberg exercise
 Complete the “NXT OnScreen Programming”
prediction
 Completed functioning
robot(s);
 [If time available:
Participation in at least one
robot challenge]
Formative assessment:
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Completion of “Driving
Course”
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Completion of a
functioning robot;
Summative assessment
written test on the nature of
robots, basic robotics, &, basic
interpretation of a simple
program
Summative Topic test
Literacy
Glossary
All practical task
instructions and
practical reports are
to be written in third
person
Numeracy
Analysis of practical
data
Methodology
Reading aloud
Note taking
Research
Analysis of data
Graphing results
Tabling data
Time concepts such as
speed, acceleration
Calculation of force,
power, gear ratios
Summarizing
information
Revision sheets
Measuring:
volume/mass/weight
Differentiation
 Students with language difficulties should have the option of presenting practical
reports verbally where required. A scribe if available can write responses for the
student.
 Students with motor difficulties should have the option of directly directing the
construction &/or programming of the robot or part(s) thereof;
 Students with profound numeracy difficulties could be allowed to use calculators
where necessary
Risk Assessment
 Standard laboratory rules should apply when handling preserved specimens.
 Students should wash their hands after handling the jars if any chemical has leaked.
 Key areas of risk outlined. Individual activities will require risk assessments, referring
to individual chemicals or safe operating procedures
Links to VELS
Science Knowledge and Understanding
Well below expected
level 3.75
Below expected level
4.25
At expected level 4.50
Above expected level
4.75
knowledge of the
consequences of change
in terms of cause and
effect applied in physical
science contexts; for
example, effect of forces
that do not always
require contact (such as
magnetism)
knowledge of the
connections between
concepts related to one
or more of energy and
time and application of
these concepts in
everyday contexts
awareness of change over
time in scientific ideas
within physical science
contexts
knowledge of factors which
have impacted on the
development of scientific
ideas over time within
physical science contexts
comparison of alternative
viewpoints about existing
scientific ideas within
physical science contexts
knowledge of the
function/s of the
components of systems;
for example, simple
machines
understanding of how a
system and/or its
components adapt to
change
awareness of how models
are used to explain
scientific phenomena and
processes related to one
or more of forces and
time
knowledge of the
relationships between
components of systems,
including understanding of
changes over time; for
example, gear systems in
regulating force and
motion
use and recognition of
limitations of models and
laws of science to explain
scientific phenomena and
processes related to one or
more of forces, energy, and
time
analysis of the impact of
factors which cause
change in living and nonliving systems over short
and long periods of time;
for example, use of
simple machines to
complete tasks
application of models and
laws of science to familiar
and unfamiliar situations
related to one or more of
forces, energy and/or
time; for example, use of
the Law of Conservation
of Energy in making
predictions about how
forces act
4.75
designs and reporting of
experimental
investigations and
simulations involving
measurement, including
identification of
procedures and
equipment which would
improve accuracy of
results
selection and application
of safety procedures
related to the use of
technical equipment and
chemicals in laboratory
and field investigations,
including risk
management
comment on the validity
of conclusions drawn
from experimental data
Science at Work
3.75
systematic collection and
analysis of data including
valid conclusions and
identification of
relationships between
variables
4.25
planning and reporting of
experimental
investigations involving
measurement, including
justification of
procedures and
equipment used
4.50
selection and application
of appropriate safety
procedures required for
laboratory and field
investigations
application of safe and
ethical procedures,
including risk management
plans for handling of
equipment and materials
systematic and accurate
collection and recording
of experimental data
evaluation of their own
role in the making of a
group-constructed
operating model of a
device, including
comments on its
effectiveness
design and construction of
a simple model, including
annotations, that illustrates
understanding of a
scientific concept
knowledge and
application of basic
safety procedures
required for laboratory
and field investigations
understanding of
different perspectives and
attitudes involved in a
scientific idea or issue of
interest, presented
through models, images
understanding of how the
work of a scientist may
have both positive and
negative outcomes for
society
group construction of a
model of a device, and
identification of their
own role in its
construction
understanding of factors
which may affect
attitudes to a scientific
idea or issue of interest
or diagrams
design and reporting of
experimental
investigations involving
measurement, including
analysis of accuracy of
results
analysis of group
effectiveness in the
construction of an
operating model of a
device, with annotations
and suggestions for
device refinement
balanced argument in
addressing a scientific
idea or issue of interest
to an audience