

ANSWERS TO PROBLEMS 



The following list comprises answers to about two thirds of the problems given 

 at the close of each section as applications of the text. This is ample to enable 

 the student to verify the correctness of his numerical applications, while enough 

 remain unanswered to cultivate self-reliance and independence of thought. 



1. Answer given. 3. Answer given. 5. 3.1 lb./in. 2 



2. Answer given. 4. 17. 7 lb./in. 2 6. .002122; 12.73 in. 



7. 16,500,000 lb./in. 2 approximately. 31. t= fod. 



8. .0044 in. approximately ;s=. 00002037. 32, Copper, 5.73 cm.; alloy, 4.27 cm. 



9. 27,708 Ib. 34. Brass, 791 Ib. ; steel, 409 Ib. 



10. .000307 in. 35, Eight -in. bolts. 



11. .0005076 in. 36. 2 in. 



12. s = .0018. crushing _ 3 



13. 5.4 in. ' shearing ~~ TT 



14. .0000104. 38. 1.7 approximately. 



15. 1005 Ib. 39, 18^. 



16. .245 in. square. 40. f-in. steel-wire rope. 



17. 5 in. for p = 16,000 lb./in. 2 54. 95.45 in. 4 



18. 113 tons at failure. 55. 441 in. 4 



19. 20.0086ft. 56. 337 in. 4 



20. 2363 lb./in. 2 57. Ill in. 4 



21. .13 in. 58. 1^ in. above base. 



22. 10,980 lb./in. 2 59. 83^ in. 4 



23. 75,280 lb./in. 2 for root area. 60. 3.36 in. from top. 



24. 10. 61. 171 in. 



25. 5.8. 62. 576| ; 364*. 



26. 17,440 Ib. 63. 3.28 in. 



27. 1,645,300 lb./in. 2 64. 51 in. 4 



28. 100 + 554 Ib. 68. Weight equal to that of table. 



29. i-in. pin. 69. First support, If ft. from 150 Ib. 



30. 2036 Ib. tension in each. weight. 



77. Maximum moment = 1920 ft.-lb. ; maximum shear = 480 Ib. 



78. Maximum moment = 4225 ft.-lb. ; maximum shear = 950 Ib. 



79. Maximum moment = 4666| ft.-lb. ; maximum shear = 833^ Ib. 



80. Maximum moment = 2200 ft.-lb. ; maximum shear = 375 Ib. 



81. Maximum moment = 750 ft.-lb. ; maximum shear = 200 Ib. 



82. Maximum moment = 3333^ ft.-lb. ; maximum shear = 8000 Ib. 



83. Maximum moment = 11,850 ft.-lb. ; maximum shear = 4100 Ib. 



93. Maximum moment = 7400 ft.-lb. ; maximum shear = 1350 Ib. 



94. Maximum moment = 24,000 ft.-lb. ; maximum shear = 4000 Ib. 



95. Maximum moment = 1250 ft.-lb. ; maximum shear = 500 Ib. 



205 



