Engineering Worksheet: Strong Shapes

Engineering lesson 17: Strong shapes: triangles, arches and beams · Set 249 · 40 questions

Engineer's tip (Triangles stay put): Triangles are rigid; trusses, towers and frames use them. A pin-jointed frame with n sides needs n − 3 corner-to-corner braces; a row of n triangles uses 2n + 1 straws. Arches squeeze (compression); beams span gaps; domes are arches turned round in a circle.

1. 1.🔺 A frame shaped like a square is made of straws joined by loose pins, with 1 corner-to-corner brace. Is it rigid or wobbly? (a) rigid (b) wobbly
2. 2.🔺 One side of a straw bridge is a row of 13 triangles standing point-up and point-down in turn, each sharing a side with the next. How many straws does it use?
3. 3.True or false: a curved stone doorway uses an arch. (a) True (b) False
4. 4.🔺 Which strong shape does a crane arm use? (a) arch (b) triangle (c) dome (d) beam
5. 5.🔺 Which strong shape does a lintel over a door use? (a) dome (b) arch (c) triangle (d) beam
6. 6.🔺 A frame shaped like a square is made of straws joined by loose pins, with 0 corner-to-corner braces. Is it rigid or wobbly? (a) wobbly (b) rigid
7. 7.🔺 A frame shaped like a hexagon is made of straws joined by loose pins, with 1 corner-to-corner brace. Is it rigid or wobbly? (a) wobbly (b) rigid
8. 8.True or false: a planetarium roof uses a dome. (a) False (b) True
9. 9.🔺 A frame shaped like a pentagon is made of straws joined by loose pins, with 2 corner-to-corner braces. Is it rigid or wobbly? (a) wobbly (b) rigid
10. 10.🔺 Which shape keeps its shape best when its corners are pinned? (a) hexagon (b) triangle (c) square (d) rectangle
11. 11.🔺 A flat frame has 6 straight sides joined by loose pins at the corners. What is the least number of corner-to-corner braces needed to make it rigid?
12. 12.🔺 One side of a straw bridge is a row of 5 triangles standing point-up and point-down in turn, each sharing a side with the next. How many straws does it use?
13. 13.Which of these uses triangles? (a) a curved stone doorway (b) a round palace roof (c) a bicycle frame (d) a fort gateway
14. 14.True or false: a slab over a canal uses a beam. (a) True (b) False
15. 15.🔺 One side of a straw bridge is a row of 2 triangles standing point-up and point-down in turn, each sharing a side with the next. How many straws does it use?
16. 16.🔺 A frame shaped like a triangle is made of straws joined by loose pins, with 0 corner-to-corner braces. Is it rigid or wobbly? (a) wobbly (b) rigid
17. 17.Which of these uses a beam? (a) a curved stone doorway (b) a roof truss (c) a plank over a drain (d) a planetarium roof
18. 18.🔺 How do engineers stop a square frame from wobbling? (a) add a diagonal brace (b) paint it (c) take off a side (d) make it bigger
19. 19.🔺 Which strong shape does a fort gateway use? (a) dome (b) triangle (c) beam (d) arch
20. 20.True or false: an igloo uses a beam. (a) True (b) False
21. 21.Which of these uses an arch? (a) a roof truss (b) a slab over a canal (c) a planetarium roof (d) a fort gateway
22. 22.🔺 One side of a straw bridge is a row of 11 triangles standing point-up and point-down in turn, each sharing a side with the next. How many straws does it use?
23. 23.True or false: a round palace roof uses triangles. (a) False (b) True
24. 24.True or false: a lintel over a door uses a beam. (a) True (b) False
25. 25.Which of these uses an arch? (a) an old stone bridge (b) a plank over a drain (c) a lintel over a door (d) a truss bridge side
26. 26.🔺 A frame shaped like a hexagon is made of straws joined by loose pins, with 0 corner-to-corner braces. Is it rigid or wobbly? (a) rigid (b) wobbly
27. 27.True or false: an old stone bridge uses an arch. (a) False (b) True
28. 28.🔺 A flat frame has 8 straight sides joined by loose pins at the corners. What is the least number of corner-to-corner braces needed to make it rigid?
29. 29.🔺 A flat frame has 9 straight sides joined by loose pins at the corners. What is the least number of corner-to-corner braces needed to make it rigid?
30. 30.Which of these uses an arch? (a) a shelf on two brackets (b) a curved stone doorway (c) a roof truss (d) an electric pylon
31. 31.🔺 Which strong shape does an electric pylon use? (a) arch (b) dome (c) triangle (d) beam
32. 32.True or false: an electric pylon uses a beam. (a) True (b) False
33. 33.🔺 One side of a straw bridge is a row of 4 triangles standing point-up and point-down in turn, each sharing a side with the next. How many straws does it use?
34. 34.🔺 A frame shaped like a pentagon is made of straws joined by loose pins, with 1 corner-to-corner brace. Is it rigid or wobbly? (a) rigid (b) wobbly
35. 35.True or false: a roof truss uses an arch. (a) False (b) True
36. 36.True or false: a crane arm uses a beam. (a) True (b) False
37. 37.Which of these uses triangles? (a) a truss bridge side (b) an igloo (c) a lintel over a door (d) a curved stone doorway
38. 38.🔺 A flat frame has 7 straight sides joined by loose pins at the corners. What is the least number of corner-to-corner braces needed to make it rigid?
39. 39.🔺 One side of a straw bridge is a row of 3 triangles standing point-up and point-down in turn, each sharing a side with the next. How many straws does it use?
40. 40.🔺 One side of a straw bridge is a row of 1 triangle standing point-up and point-down in turn, each sharing a side with the next. How many straws does it use?

Free engineering lessons, practice and worksheets at talentjr.in/engineering-for-kids