Engineering Worksheet: Strong Shapes

Engineering lesson 17: Strong shapes: triangles, arches and beams · Set 138 · 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 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?
2. 2.Which of these uses triangles? (a) an electric pylon (b) a shelf on two brackets (c) a curved stone doorway (d) a round palace roof
3. 3.🔺 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
4. 4.Which of these uses triangles? (a) a curved stone doorway (b) a fort gateway (c) a bicycle frame (d) an old stone bridge
5. 5.Which of these uses an arch? (a) a curved stone doorway (b) an igloo (c) a slab over a canal (d) a planetarium roof
6. 6.🔺 One side of a straw bridge is a row of 14 triangles standing point-up and point-down in turn, each sharing a side with the next. How many straws does it use?
7. 7.True or false: a fort gateway uses a beam. (a) True (b) False
8. 8.🔺 Which strong shape does a truss bridge side use? (a) triangle (b) beam (c) arch (d) dome
9. 9.🔺 A beam bends under a load. Its top side is … (a) not affected (b) floating (c) squeezed (compression) (d) stretched (tension)
10. 10.🔺 Which strong shape does a roof truss use? (a) dome (b) beam (c) triangle (d) arch
11. 11.Which of these uses a dome? (a) an old stone bridge (b) a planetarium roof (c) a plank over a drain (d) an electric pylon
12. 12.🔺 Which strong shape does a bicycle frame use? (a) arch (b) dome (c) triangle (d) beam
13. 13.True or false: a roof truss uses triangles. (a) True (b) False
14. 14.🔺 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?
15. 15.🔺 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?
16. 16.🔺 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
17. 17.Which of these uses a beam? (a) a slab over a canal (b) a round palace roof (c) a fort gateway (d) an electric pylon
18. 18.🔺 Which shape keeps its shape best when its corners are pinned? (a) square (b) rectangle (c) hexagon (d) triangle
19. 19.True or false: a curved stone doorway uses an arch. (a) False (b) True
20. 20.🔺 One side of a straw bridge is a row of 12 triangles standing point-up and point-down in turn, each sharing a side with the next. How many straws does it use?
21. 21.🔺 Why can an arch carry heavy loads? (a) it is hollow (b) it bends easily (c) it is very light (d) it works in compression
22. 22.🔺 Which strong shape does a crane arm use? (a) dome (b) arch (c) triangle (d) beam
23. 23.🔺 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
24. 24.🔺 A flat frame has 5 straight sides joined by loose pins at the corners. What is the least number of corner-to-corner braces needed to make it rigid?
25. 25.🔺 A flat frame has 10 straight sides joined by loose pins at the corners. What is the least number of corner-to-corner braces needed to make it rigid?
26. 26.Which of these uses triangles? (a) a plank over a drain (b) a round palace roof (c) a fort gateway (d) a roof truss
27. 27.True or false: an electric pylon uses triangles. (a) True (b) False
28. 28.🔺 One side of a straw bridge is a row of 9 triangles standing point-up and point-down in turn, each sharing a side with the next. How many straws does it use?
29. 29.🔺 Which strong shape does an electric pylon use? (a) triangle (b) arch (c) beam (d) dome
30. 30.🔺 Which strong shape does a planetarium roof use? (a) arch (b) triangle (c) dome (d) beam
31. 31.🔺 Which strong shape does a slab over a canal use? (a) arch (b) beam (c) dome (d) triangle
32. 32.🔺 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?
33. 33.🔺 A flat frame has 12 straight sides joined by loose pins at the corners. What is the least number of corner-to-corner braces needed to make it rigid?
34. 34.True or false: a shelf on two brackets uses a dome. (a) False (b) True
35. 35.🔺 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
36. 36.🔺 One side of a straw bridge is a row of 15 triangles standing point-up and point-down in turn, each sharing a side with the next. How many straws does it use?
37. 37.True or false: a crane arm uses triangles. (a) True (b) False
38. 38.True or false: an old stone bridge uses an arch. (a) False (b) True
39. 39.🔺 Which strong shape does a shelf on two brackets use? (a) dome (b) triangle (c) arch (d) beam
40. 40.🔺 Which strong shape does a fort gateway use? (a) beam (b) triangle (c) dome (d) arch

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