Homework Help is Here – Start Your Trial Now!
Engineering
Mechanical Engineering
Problem 1: Warm-ups a) Four strain gauges are bonded to a cylindrical bar as shown below. What signal is generated by each gauge when a small torque is applied to the bar? Positive = tension. (i) (ii) (!!!) (iv) (i) Positive Negative Zero Positive Positive Negative Zero Negative Zero (iv) Positive Negative Zero b) Your team has completed the design of a structural component and calculated the most critical safety factor. Which of the following factors, by itself, could lead to a change in the calculated safety factor? A new, previously unanticipated failure mode is identified. The manufacturing tolerances are changed. A new material is specified for the component. The component is deployed in a new environment with a higher cost of failure. ☐ New laws governing the safety of the component go into effect. c) The fatigue life of bolted joints depends on how much they are tightened. You have determined that by increasing the specified preload (σm) on a bolted joint by 20%, the stress amplitude σ will be reduced by 20%. Assuming σm and σa were roughly equal to begin with, Is this a good idea? Yes or No. d) Someone overtightened the bolted joint shown and now it's too tight to turn! Should you: ☐ heat up the assembly, or cool down the assembly to get it unstuck? e) Rank the four stress states shown below in order of increasing safety factor for the two failure criteria given. Assume the circle shown is the largest Mohr's circle for each stress state. Brass bolt and nut, a = 18E-6 1/K Steel plates a=11E-6 1/K

Problem 1: Warm-ups a) Four strain gauges are bonded to a cylindrical bar as shown below. What signal is generated by each gauge when a small torque is applied to the bar? Positive = tension. (i) (ii) (!!!) (iv) (i) Positive Negative Zero Positive Positive Negative Zero Negative Zero (iv) Positive Negative Zero b) Your team has completed the design of a structural component and calculated the most critical safety factor. Which of the following factors, by itself, could lead to a change in the calculated safety factor? A new, previously unanticipated failure mode is identified. The manufacturing tolerances are changed. A new material is specified for the component. The component is deployed in a new environment with a higher cost of failure. ☐ New laws governing the safety of the component go into effect. c) The fatigue life of bolted joints depends on how much they are tightened. You have determined that by increasing the specified preload (σm) on a bolted joint by 20%, the stress amplitude σ will be reduced by 20%. Assuming σm and σa were roughly equal to begin with, Is this a good idea? Yes or No. d) Someone overtightened the bolted joint shown and now it's too tight to turn! Should you: ☐ heat up the assembly, or cool down the assembly to get it unstuck? e) Rank the four stress states shown below in order of increasing safety factor for the two failure criteria given. Assume the circle shown is the largest Mohr's circle for each stress state. Brass bolt and nut, a = 18E-6 1/K Steel plates a=11E-6 1/K

Elements Of Electromagnetics
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
See similar textbooks
icon
Related questions
Question
1
Problem 1: Warm-ups a) Four strain gauges are bonded to a cylindrical bar as shown below. What signal is generated by each gauge when a small torque is applied to the bar? Positive = tension. (i) (ii) (iii) (iv) (i) Positive Negative Zero (ii) (iv) Positive Negative Zero Positive Negative Zero Positive Negative Zero b) Your team has completed the design of a structural component and calculated the most critical safety factor. Which of the following factors, by itself, could lead to a change in the calculated safety factor? ☐ ☐ ☐ A new, previously unanticipated failure mode is identified. The manufacturing tolerances are changed. A new material is specified for the component. The component is deployed in a new environment with a higher cost of failure. ☐ New laws governing the safety of the component go into effect. c) The fatigue life of bolted joints depends on how much they are tightened. You have determined that by increasing the specified preload (σm) on a bolted joint by 20%, the stress amplitude σ will be reduced by 20%. Assuming σm and σa were roughly equal to begin with, Is this a good idea? Yes or No. d) Someone overtightened the bolted joint shown and now it's too tight to turn! Should you: ☐ heat up the assembly, or ☐ cool down the assembly to get it unstuck? e) Rank the four stress states shown below in order of increasing safety factor for the two failure criteria given. Assume the circle shown is the largest Mohr's circle for each stress state. Brass bolt and nut, a = 18E-6 1/K Steel plates a = 11E-6 1/K (j) (ii) (iii) (iv) Max. shear stress criterion: Most likely to fail Least likely to fail → Max. normal stress criterion: (assume Suc =2Sut) Most likely to fail Least likely to fail →
Transcribed Image Text:Problem 1: Warm-ups a) Four strain gauges are bonded to a cylindrical bar as shown below. What signal is generated by each gauge when a small torque is applied to the bar? Positive = tension. (i) (ii) (iii) (iv) (i) Positive Negative Zero (ii) (iv) Positive Negative Zero Positive Negative Zero Positive Negative Zero b) Your team has completed the design of a structural component and calculated the most critical safety factor. Which of the following factors, by itself, could lead to a change in the calculated safety factor? ☐ ☐ ☐ A new, previously unanticipated failure mode is identified. The manufacturing tolerances are changed. A new material is specified for the component. The component is deployed in a new environment with a higher cost of failure. ☐ New laws governing the safety of the component go into effect. c) The fatigue life of bolted joints depends on how much they are tightened. You have determined that by increasing the specified preload (σm) on a bolted joint by 20%, the stress amplitude σ will be reduced by 20%. Assuming σm and σa were roughly equal to begin with, Is this a good idea? Yes or No. d) Someone overtightened the bolted joint shown and now it's too tight to turn! Should you: ☐ heat up the assembly, or ☐ cool down the assembly to get it unstuck? e) Rank the four stress states shown below in order of increasing safety factor for the two failure criteria given. Assume the circle shown is the largest Mohr's circle for each stress state. Brass bolt and nut, a = 18E-6 1/K Steel plates a = 11E-6 1/K (j) (ii) (iii) (iv) Max. shear stress criterion: Most likely to fail Least likely to fail → Max. normal stress criterion: (assume Suc =2Sut) Most likely to fail Least likely to fail →
Expert Solution
steps

Step by step

Solved in 4 steps with 4 images

SEE SOLUTIONCheck out a sample Q&A here
Blurred answer
Knowledge Booster
Strain Transformation
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, mechanical-engineering and related others by exploring similar questions and additional content below.
Similar questions
  • SEE MORE QUESTIONS
Recommended textbooks for you
Elements Of Electromagnetics
Elements Of Electromagnetics
Mechanical Engineering
ISBN:
9780190698614
Author:
Sadiku, Matthew N. O.
Publisher:
Oxford University Press
Mechanics of Materials (10th Edition)
Mechanics of Materials (10th Edition)
Mechanical Engineering
ISBN:
9780134319650
Author:
Russell C. Hibbeler
Publisher:
PEARSON
Thermodynamics: An Engineering Approach
Thermodynamics: An Engineering Approach
Mechanical Engineering
ISBN:
9781259822674
Author:
Yunus A. Cengel Dr., Michael A. Boles
Publisher:
McGraw-Hill Education
Control Systems Engineering
Control Systems Engineering
Mechanical Engineering
ISBN:
9781118170519
Author:
Norman S. Nise
Publisher:
WILEY
Mechanics of Materials (MindTap Course List)
Mechanics of Materials (MindTap Course List)
Mechanical Engineering
ISBN:
9781337093347
Author:
Barry J. Goodno, James M. Gere
Publisher:
Cengage Learning
Engineering Mechanics: Statics
Engineering Mechanics: Statics
Mechanical Engineering
ISBN:
9781118807330
Author:
James L. Meriam, L. G. Kraige, J. N. Bolton
Publisher:
WILEY
SEE MORE TEXTBOOKS