← Strong shapes: triangles, arches and beams lesson New set →

Engineering Worksheet: Strong Shapes

Engineering lesson 17: Strong shapes: triangles, arches and beams · Set 431 · 40 questions
TalentJR

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.

NameDateTime takenScore ___ / 40
  1. 1.🔺 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
  2. 2.🔺 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?
  3. 3.🔺 Which strong shape does a planetarium roof use? (a) arch (b) beam (c) dome (d) triangle
  4. 4.🔺 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?
  5. 5.🔺 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?
  6. 6.Which of these uses a dome? (a) a lintel over a door (b) a round palace roof (c) a plank over a drain (d) a slab over a canal
  7. 7.🔺 Why can an arch carry heavy loads? (a) it is hollow (b) it bends easily (c) it works in compression (d) it is very light
  8. 8.Which of these uses an arch? (a) a fort gateway (b) a slab over a canal (c) an electric pylon (d) a plank over a drain
  9. 9.True or false: an electric pylon uses a dome. (a) True (b) False
  10. 10.True or false: a bicycle frame uses triangles. (a) True (b) False
  11. 11.🔺 Which strong shape does an old stone bridge use? (a) dome (b) triangle (c) beam (d) arch
  12. 12.🔺 Which strong shape does a crane arm use? (a) triangle (b) arch (c) dome (d) beam
  13. 13.🔺 Which shape keeps its shape best when its corners are pinned? (a) triangle (b) rectangle (c) square (d) hexagon
  14. 14.🔺 Which strong shape does a curved stone doorway use? (a) arch (b) triangle (c) beam (d) dome
  15. 15.🔺 A flat frame has 4 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.Which of these uses an arch? (a) a plank over a drain (b) a curved stone doorway (c) a round palace roof (d) a bicycle frame
  17. 17.🔺 Which strong shape does a slab over a canal use? (a) triangle (b) beam (c) dome (d) arch
  18. 18.🔺 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) rigid (b) wobbly
  19. 19.Which of these uses triangles? (a) a lintel over a door (b) a truss bridge side (c) a fort gateway (d) an igloo
  20. 20.True or false: a shelf on two brackets uses a beam. (a) False (b) True
  21. 21.Which of these uses a dome? (a) an electric pylon (b) a truss bridge side (c) an igloo (d) a plank over a drain
  22. 22.🔺 Which strong shape does a plank over a drain use? (a) dome (b) arch (c) beam (d) triangle
  23. 23.🔺 Which strong shape does a bicycle frame use? (a) beam (b) arch (c) dome (d) triangle
  24. 24.🔺 A beam bends under a load. Its top side is … (a) not affected (b) floating (c) squeezed (compression) (d) stretched (tension)
  25. 25.True or false: a fort gateway uses a dome. (a) True (b) False
  26. 26.🔺 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?
  27. 27.🔺 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?
  28. 28.Which of these uses triangles? (a) an igloo (b) a round palace roof (c) a bicycle frame (d) a lintel over a door
  29. 29.True or false: an old stone bridge uses triangles. (a) True (b) False
  30. 30.Which of these uses a dome? (a) a planetarium roof (b) a slab over a canal (c) a truss bridge side (d) a shelf on two brackets
  31. 31.🔺 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?
  32. 32.🔺 Which strong shape does a round palace roof use? (a) beam (b) arch (c) triangle (d) dome
  33. 33.🔺 Which strong shape does a roof truss use? (a) triangle (b) arch (c) beam (d) dome
  34. 34.🔺 Which strong shape does a truss bridge side use? (a) arch (b) triangle (c) dome (d) beam
  35. 35.🔺 Which strong shape does a lintel over a door use? (a) dome (b) triangle (c) beam (d) arch
  36. 36.🔺 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?
  37. 37.True or false: a slab over a canal uses a beam. (a) False (b) True
  38. 38.🔺 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?
  39. 39.True or false: a plank over a drain uses triangles. (a) False (b) True
  40. 40.🔺 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?

Answer key

  1. wobbly
  2. 7
  3. dome
  4. 9
  5. 31
  6. a round palace roof
  7. it works in compression
  8. a fort gateway
  9. False
  10. True
  11. arch
  12. triangle
  13. triangle
  14. arch
  15. 1
  16. a curved stone doorway
  17. beam
  18. rigid
  19. a truss bridge side
  20. True
  21. an igloo
  22. beam
  23. triangle
  24. squeezed (compression)
  25. False
  26. 11
  27. 25
  28. a bicycle frame
  29. False
  30. a planetarium roof
  31. 4
  32. dome
  33. triangle
  34. triangle
  35. beam
  36. 7
  37. True
  38. 27
  39. False
  40. 3

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