3. A severe service valve spring is to be manufactured from unpeened ASTM A230 steel wire in standard W & M sizes operating continouosly between 20 Ibf and 30 lbf. The valve lift is 0.3 in. The spring index is 10. The ultimate tensile strength of the wire material is 205,000 lbf/in?. The factor of safety is 1.5. The minimum design fatigue service life is 10,000,000 cycles. A. The wire diameter is most nearly C. 0.21 in А. О.12 B. The spring constant is most nearly A. 10 Ibf/in? B. 21 Ibf/in? C. If the ends are squared and ground, the minimum number of active coils is most nearly А. 4.7 B. 0.15 in D. 0.28 in C. 33 Ibf/in? D. 48 Ibf/in? В. 5.2 D. The minimum total number of coils is most nearly В. 6.9 С. 6.4 D.8.6 А. 6.2 С. 7,8 D. 8.4

3. A severe service valve spring is to be manufactured from unpeened ASTM A230 steel wire in standard W & M sizes operating continouosly between 20 Ibf and 30 lbf. The valve lift is 0.3 in. The spring index is 10. The ultimate tensile strength of the wire material is 205,000 lbf/in?. The factor of safety is 1.5. The minimum design fatigue service life is 10,000,000 cycles. A. The wire diameter is most nearly C. 0.21 in А. О.12 B. The spring constant is most nearly A. 10 Ibf/in? B. 21 Ibf/in? C. If the ends are squared and ground, the minimum number of active coils is most nearly А. 4.7 B. 0.15 in D. 0.28 in C. 33 Ibf/in? D. 48 Ibf/in? В. 5.2 D. The minimum total number of coils is most nearly В. 6.9 С. 6.4 D.8.6 А. 6.2 С. 7,8 D. 8.4

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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