Gr 8-Technology-Study Guide

Í2’È-E-TEC-SG01DÎ

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TECHNOLOGY STUDY GUIDE

Grade 8

A member of the FUTURELEARN group

Technology Study guide

1808-E-TEC-SG01

Í2(È-E-TEC-SG01FÎ

Grade 8

CAPS aligned

FI le Roux JC le Roux J Lubbinge HA Saaiman J Saaiman A Schwartz

Study Guide G08 ~ Technology

Contents PREFACE............................................................................................................................ 7 INTRODUCTION.................................................................................................................. 7 STUDY TIPS........................................................................................................................ 7 SUBJECT CONTENT AND PLANNING.............................................................................. 8 TERM 1: UNIT 1: Design skills.......................................................................................... 9 LESSON 1: Design process.................................................................................. 13 Activity 1................................................................................................................. 15 LESSON 2: Safety................................................................................................. 15 Activity 2................................................................................................................. 16 TERM 1: UNIT 2: Structures............................................................................................. 17 LESSON 3: Frame structures................................................................................ 18 Activity 3................................................................................................................. 20 LESSON 4: Structural members in roof trusses.................................................... 20 Activity 4................................................................................................................. 21 LESSON 5: Forces................................................................................................ 23 Activity 5.1............................................................................................................. 25 Activity 5.2............................................................................................................. 25 LESSON 6: Reinforcing of structures.................................................................... 26 Activity 6.1............................................................................................................. 26 Activity 6.2............................................................................................................. 28 Activity 6.3............................................................................................................. 29 LESSON 7: Structures spanning a space.............................................................. 31 Activity 7................................................................................................................. 34 LESSON 8: Types of structures............................................................................. 34 Activity 8................................................................................................................. 41 LESSON 9: Structural failure................................................................................. 41 Activity 9................................................................................................................. 42 TERM 1: UNIT 3: Communication skills......................................................................... 44 LESSON 10: Graphical communication ................................................................ 45 Activity 10.1........................................................................................................... 52 Activity 10.2........................................................................................................... 66 Activity 10.3........................................................................................................... 71 Activity 10.4........................................................................................................... 71 Activity 10.5........................................................................................................... 76 Activity 10.6........................................................................................................... 81 Activity 10.7........................................................................................................... 89 Activity 10.8........................................................................................................... 96

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Study Guide G08 ~ Technology

TERM 1: UNIT 4: Mechanical systems and control..................................................... 103 LESSON 11: Simple machines............................................................................ 104 Activity 11............................................................................................................. 105 LESSON 12: Gears............................................................................................. 106 Activity 12.1......................................................................................................... 107 Activity 12.2......................................................................................................... 109 LESSON 13: Mechanisms that change direction of movement........................... 110 Activity 13.............................................................................................................111 PRACTICAL ASSESSMENT TASK..................................................................... 113 TERM 2: UNIT 5: Impact of technology and processing............................................. 126 LESSON 14: The positive impact of technology.................................................. 127 Activity 14............................................................................................................ 129 LESSON 15: The negative impact of technology................................................. 130 Activity 15............................................................................................................ 131 LESSON 16: Reducing the negative impact of technology................................. 131 Activity 16............................................................................................................ 132 PRACTICAL ASSESSMENT TASK..................................................................... 135 TERM 3: UNIT 6: Mechanical systems and control..................................................... 143 LESSON 17: Simple machanisms: Levers.......................................................... 144 Activity 17............................................................................................................ 144 LESSON 18: Gears............................................................................................. 151 Activity 18............................................................................................................ 155 LESSON 19: Impact of technology: Mining......................................................... 156 Activity 19............................................................................................................ 157 PRACTICAL ASSESSMENT TASK..................................................................... 158 TERM 4: UNIT 7: Electrical systems and control........................................................ 171 LESSON 20: Simple circuit components............................................................. 172 Activity 20............................................................................................................ 176 LESSON 21: Correct connections....................................................................... 176 Activity 21............................................................................................................ 177 LESSON 22: Electrical components and their symbols....................................... 179 Activity 22............................................................................................................ 179 LESSON 23: Impact of bias in technology........................................................... 180 Activity 23............................................................................................................ 182 LESSON 24: Electrochemical cells...................................................................... 182 Activity 24............................................................................................................ 185 LESSON 25: Photovoltaic cells........................................................................... 187 Activity 25............................................................................................................ 188 LESSON 26: Generating electricity..................................................................... 188 Activity 26............................................................................................................ 193 LESSON 27: Alternating current.......................................................................... 194 LESSON 28: Electrical circuits and control.......................................................... 195 © Impaq

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Study Guide G08 ~ Technology

PRACTICAL ASSESSMENT TASK..................................................................... 199 ADDENDUM A: Important terminology......................................................................... 205 ADDENDUM B: Squared paper...................................................................................... 207 ADDENDUM C: Isometric paper.................................................................................... 209 ADDENDUM D: Drawing sheet...................................................................................... 211 ADDENDUM E: Colour images...................................................................................... 213

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Study Guide G08 ~ Technology

SUBJECT CONTENT AND PLANNING UNIT 1

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LESSON TERM 1 LESSON 1: Design process LESSON 2: Safety LESSON 3: Frame structures LESSON 4: Structural members in roof trusses LESSON 5: Forces LESSON 6: Reinforcing of structures LESSON 7: Structures spanning a space LESSON 8: Types of structures LESSON 9: Structural failure LESSON 10: Graphical communication LESSON 11: Simple machines LESSON 12: Gears LESSON 13: Mechanisms that change direction of movement PRACTICAL ASSESSMENT TASK (PAT) TERM 2 LESSON 14: The positive impact of technology LESSON 15: The negative impact of technology LESSON 16: Reducing the negative impact of technology PRACTICAL ASSESSMENT TASK (PAT) TERM 3 LESSON 17: Levers LESSON 18: Gears (continued) LESSON 19: Impact of technology: mining PRACTICAL ASSESSMENT TASK (PAT) TERM 4 LESSON 20: Simple circuit components LESSON 21: Correct connections LESSON 22: Electrical components and their symbols LESSON 23: Impact of bias in technology LESSON 24: Electrochemical cells LESSON 25: Photovoltaic cells LESSON 26: Generating electricity LESSON 27: Alternating current LESSON 28: Electrical circuits and control PRACTICAL ASSESSMENT TASK (PAT)

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Study Guide G08 ~ Technology Unit

TERM 1

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UNIT 1: Design skills

Learning objectives After you have completed this unit, you must be able to demonstrate your knowledge and understanding of: Design process • Investigate • Design • Make or manufacture • Evaluate • Communication Safety The main causes of accidents • General safety rules for practical technology work • Safety regulations regarding electricity • Gas • Safety precautions when using cutting tools • Safety precautions related to cleaning agents and medicine

Introduction

Technology is the use of knowledge, skills and resources to provide practical solutions (objects) to solve people’s problems or meet their needs. Technology contributes to human support and comfort, while taking social and environmental factors into consideration.

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Study Guide G08 ~ Technology

IMPORTANT TERMINOLOGY Analyse To closely study or examine a problem, need or item.

Annotate/Label To provide work or sketches with notes and

explanatory remarks.

Artistic drawing When advanced techniques such as colour, texture, shading, shadows and perspective are used to create a drawing that resembles reality.

Bias A tendency to support or oppose a particular person or thing in an unfair way by allowing personal opinions to influence your judgement.

Communicate To share information with others by speaking,

writing, drawing or using models or products.

Constraints Aspects that limit conditions within which the work

or solution must be developed, e.g., time,

materials, cost.

Creative Producing or using original and unusual ideas.

Describe To say or write what something or someone is like.

Design To make a provisional plan or drawing (a possible solution).

Design brief A short statement of a problem or need. For

example, a plastic container for packaging.

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Design process The activity of solving problems through ideas.

STEP 1: Investigate STEP 2: Design STEP 3: Manufacture STEP 4: Evaluate STEP 5: Communicate

Design specifications

The criteria of the final solution, e.g., shape, size.

Evaluate To judge the quality or effectiveness of a product or idea.

Flow chart A diagram that allows you to identify every step in the manufacturing process.

Investigate To carefully examine a problem, need or want.

Isometric projection A 3-D drawing that uses lines drawn at 30°.

Make To produce or manufacture something.

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Needs Things that a person must have for a satisfactory life.

Orthographic projection A 2-D drawing used to produce a working

drawing, usually showing three separate views of

the same object.

Portfolio A systematic and organised collection of

someone’s work.

Problem A situation, person or thing that needs attention

and needs to be solved or addressed.

Prototype The first version of a product.

Questionnaire A set of questions used to find out people’s views about something.

Survey Research carried out by questioning.

Wants To desire a particular thing (which you can live a

satisfactory life without).

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Study Guide G08 ~ Technology Unit

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LESSON 1: Design process Below is an example of the steps involved in the design process.

STEP 1: Investigate 1.1 1.2 Safety 1.3

Identify the problem (need/want) ...……………………………………………………………………………………………………...................

Analyse EXISTING products on: Suitability of materials Investigation strategy

Fitness for purpose

Cost

Manufacturing method

Use a variety of available technologies and methods to: • locate (library referencing systems, internet searches, indexes, magazines, shops) • collect (questionnaires, data collection forms, literature surveys) • test and compare the properties of a product • sort and verify the information Circle or underline the method you used.

STEP 2: Design 2.1 Design brief (Short written idea including outline of the problem, who is affected, how the product will be used, reliability and the impact on the environment.) ..…………...............……………………………………………………….…..……………………………....

2.2 Design ideas (Use the design brief and freehand drawings to find several solutions. Choose the best solution.) ……....……………………………………………………………………………………………..…………… ….............………………………………………………………………………………………………………

2.3 Design specifications (More detailed than the design brief.)

List of features of product/description (Details of size, shape, colour, etc.)

Materials (What will the product be made from?)

Safety

Cost

Quality standards (Does the product meet a certain standard?)

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STEP 3: Make/manufacture 3.1

Planning

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Formal drawing showing • dimensions and quantities (on separate folio paper) • Resource lists: (tools/ equipment) ................................................. • ................................................. .................................................

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Manufacturing process (how it is made) Formal drawings showing dimensions and quantities (on separate folio paper) Resource lists: (tools/equipment) ..................................................................................... .....................................................................................

Manufacturing skills (Skills needed to manufacture, e.g., measuring.) ..................................................................................... .....................................................................................

Safe working practices (Demonstrate a knowledge and understanding of safe working practices.) .....................................................................................

STEP 4: Evaluate 4.1 4.2 4.2.1 mm

Who is doing the evaluation? .............................................................................................................................................................

How are you going to evaluate? .............................................................................................................................................................

Evaluate the final product by comparing it with: • design brief • specifications

mm 4.2.2 mm

Evaluate the manufacturing process with mm regard to efficient: • work procedures • skills • time management

STEP 5: Communicate 5.1

Prepare presentation • Existing drawings • All written information (design brief, poster, PowerPoint or slides including reasoning for design) 5.2 Comments on design process • Was design/project successful/good?

• ……………………………………………………………….................................................…

• Reasons for the above • ………………………………………………………………….….............................…………

• Suggestions to improve design …………………………………………………………………….............................………...…

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Study Guide G08 ~ Technology Unit

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Activity 1 Design process Instructions Design a means of transport made of wood to carry five learners across a river every day.

Name the five steps of the design process to follow when a new product is developed to solve a problem.

LESSON 2: Safety 2.

The main causes of accidents • • •

Reckless or unsafe acts Faults in mechanical systems Faults in electrical systems

2.1

General safety rules for practical technology work • Obey all safety rules when using electrical apparatus, kitchen appliances and machinery.

• Do not play around with the power switch/power button.

• Always keep hands and fingers clear of moving parts, blades or sharp edges.

• Ensure that the machine is switched off and that all moving parts have stopped before making any adjustments.

2.2

Safety regulations regarding electricity • Ensure that the electrical apparatus is connected correctly.

• Know where the main switch or emergency cut-off switch is located.

• Report any defects of/damage to electrical apparatus.

• Examine all cables, wires or cords for damage and replace immediately if necessary.

• Check that the power source is switched off before connecting plugs to/ disconnecting plugs from a wall socket.

• Never work with electricity near water.

• Never overload the wall socket with too many plugs.

2.3 Gas Gas leaks may cause the following accidents: • explosions • fires • poisoning

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Study Guide G08 ~ Technology

If you smell gas: • Make sure there are no open gas valves.

• Close the main valve on top of the gas cylinder.

• Open all windows and doors.

• Never look for a gas leak with an open flame like a candle.

2.4

Safety precautions when using cutting tools • Prevent cutting tool accidents by:

o keeping tools in a good condition

o handling tools correctly • Use the correct cutting tool for the job intended.

• Handle cutting tools with care. Don’t drop them.

• DO NOT check the sharpness of a blade with your finger.

• DO NOT carry cutting tools with sharp blades or edges in your pocket.

• Store cutting tools in a safe place after use.

• Carry cutting tools with the sharp edge towards the ground or pointing away from your body.

• DO NOT run around with cutting tools.

2.5

Safety precautions related to cleaning agents and medicine Cleaning agents (methylated spirits, benzene, paraffin, bleach, etc.) must: • never be stored with food • be kept out of reach of children • be clearly marked • be closed properly • be kept away from open flames (cigarettes, lighters, fires, etc.) as they are often highly flammable

Activity 2 Instructions 1.

Name the THREE main causes of accidents.

2.

List FOUR safety regulations to apply when handling a knife.

3.

Connect a plug as shown below.

• L: Live Brown or red (bottom right) • N: Neutral Blue or black (bottom left) • Earth: Green or green and yellow or only copper wire

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*Refer to addendum E for colour images.

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Study Guide G08 ~ Technology Unit

TERM 1

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UNIT 2: Structures

Learning objectives After you have completed this unit, you must be able to demonstrate your knowledge and understanding of: Frame structures • Definition of frame structures • Types of frames • Purpose of structural members in roof trusses Structural members in roof trusses • Types of structural members in roof trusses • Rafter ties in trusses Forces Reinforcing of structures • Triangulation • Internal cross-bracing Structures spanning a space • Structural members of structures spanning a space Types of structures • Bridges • Arches • Cantilevers Structural failure

Introduction

Structures are part of everyday life and serve a variety of purposes. Different types of forces also act on structures, which is why certain structures need to be reinforced to withstand the forces being exerted.

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Study Guide G08 ~ Technology

IMPORTANT TERMINOLOGY A structural member is a specific part or component used to make a structure, e.g., columns, beams and struts. Each member performs a specific function in a structure.

Roof trusses are an example of an inside frame

Modern designes feature frame structures as part of their design

LESSON 3: Frame structures 3.1

Definition of frame structures Frame structures are different structural members joined together to form a frame that can withstand forces and provide support. The frame is usually made of wood, steel or reinforced concrete. The structure supports its own weight as well as the load it carries.

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3.2

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Types of frames

Inside frame: • The frame is sometimes hidden; e.g., roof trusses hidden underneath the tiles of a roof or corrugated sheeting.

• Most high-rise buildings have an internal frame structure that is not visible after the construction of the building is completed.

Outside/Visible frame: • Modern designers feature the frame structure as part of their design.

3.3

Purpose of structural members in roof trusses

Roofs are supported by triangular frame structures called roof trusses. The structural members are usually made of wood or steel. The purposes of the different structural members vary as each member is designed for a specific purpose.

All structural members help to: • withstand forces in a structure • support structures • add to the strength of a structure The following table compares the advantages and disadvantages for the use of wood and steel as structural members.

Advantages

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Disadvantages • • •

Steel structural members Stronger than wood Strong, lightweight material Carry bigger loads than wood Withstand strong winds Do not bend or become crooked Quickly assembled Used in all weather conditions Prone to rust Must be treated with anti-rust agents to protect it Weaken with time

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Wood structural members Cheaper than concrete Lightweight material Durable, long lasting Flexible material Good insulating properties Has an attractive natural finish Easy to use Must be protected against insects and moisture; e.g., with creosote or varnish Rot in the presence of water and sunlight

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