Question

1. In a mechanical design, it is recommended to use standard size/dimension to overcome uncertainties in stress or material strength.
A. True
B. False
2. Steels' surface fatigue strength can be correlated to their Brinell hardnesses.
A. True
B. False
3. If a material point has three principal stresses 01 = 02 = 03 = 300kpsi, then the maximum shear stress is Tmax = 150kpsi.
A. True
B. False
4. The endurance limit of a material is independent on the size of a part.
A. True
B. False
5. The tensile stress in a bolt is usually calculated through tensile force divided by area of unthreaded rod's cross-section area.
A. True
B. False
6. Edge shear-out or tear-out is one failure mode in bolted or riveted joints.
A. True
B. False
7. Pretension of bolts can be controlled by a torque wrench.
A. True
B. False
8. The material ultimate tensile strength of a spring coil is dependent on its coil diameter.
A. True
B. False
9. Adhesive joints are much stronger in tensile loading than shear loading.
A. True
B. False
10. The dominated loading condition in a helical spring is torsion along coils.
A. True
B. False
11. The principal advantage of conical springs is that the its spring rate is non-linear.
A. True
B. False
12. The dimensions of a bearing is coded by two-digit series numbers according to ABMA, one digit for width and the other one for diameter.
A. True
B. False
13. Three key things to determine selection of bearing are load, life and reliability.
A. True
B. False
14. Straight roller bearings can carry large radial loads and small amount of axial load.
A. True
B. False
15. In the AGMA method of gear analysis, gear strength values are the true material strengths.
A. True
B. False
16. A planetary gear train allows for two degrees of freedom.
A. True
B. False

Answer 1

Answer:

1. A.True

2. B.False

3. B.False

4. A.True

5. A.True

6. A.True

7. A.True

8. B.False

9. B.False

10. A.True

11. B.False

12. A.True

13. A.True

14. B.False

15. B.False

16. A.True

Explanation:

Most steels have endurance and fatigue limit about half the Tensile strength. Tensile strength of material is the limit of stress at which material then breaks. The tensile stress in a bolt is calculated through tensile force.