Activity 6 Test 2-D shapes for stability Learner’s Book page 18 Guidelines to implement this activity
• This is a group activity. • The learners use the straws to build the shapes illustrated in their books. • If you cannot get hold of plasticine or modelling clay, use sticky tape to join the straws at the corners.
Background knowledge
When designers create corner joints in a structure they need to strengthen them. The bicycle frame is an excellent example of triangulation. It is strong because it is made of steel tubing formed into a triangular shape. How are the different tubes joined together? In modern bicycles they are welded together but on older bikes you will notice that the joints have special thicker pieces to strengthen them. These are metal sleeves slightly larger than the diameter of the tubes of the frame. They are called lugs and they slide over the steel tubes. The two parts are joined together by a process called brazing which is slightly different from welding in that the gap between the tube and the lug is filled with molten brass.
Assessment guidelines
• This activity is intended for informal assessment. • Use the checklist below to assess learners. Give learners feedback on their performance to prepare them for formal assessment.
Criteria
The learner(s) can: recognise ways of strengthening a structure. explain what is meant by triangulation.
Extension/Extension activity
You can strengthen corner joints by cutting, folding and gluing a piece of card. Using this method, it is possible to make a simple picture frame. The frame itself can be made of pieces of wood with a 15 mm square cross-section. Use strong card to make the corner joint and then paint the frame to give it a bright appearance. If you use corrugated card for the corner
joints, it will also give it an interesting texture. • Can the learners follow instructions in order to make the corner strengthening pieces? • Can the learners recognise similar applications of this process?
46 Yes Partly No
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61
