Answer:
a)

b)
Alternating and mean forces on the bolt are 0.85 kN and 29.65 kN respectively.
Mean and alternating stresses in the bulk of the bolt are 378 MPa and 10 MPa.
c)
Safety factor = 5.5
Explanation:
Basic Dimension of Isometric Screw thread" is considered for analysis.
At Nominal diameter, d = 12 mm ,
,
, 
Rolled threads; 
Answer:A. 40% B.50% C. 60% Od 70%
Explanation:A. True B. False
Answer:
1) 4.361 x 10 raised to power 8 revolutions
2) 1.744 x 10 raised to power 9 firings
3) 2.18 x 10 raised to power 8 intake strokes
Explanation:
The step by step explanation is as shown in the attachment
Answer:
The condition does not hold for a compression test
Explanation:
For a compression test the engineering stress - strain curve is higher than the actual stress-strain curve and this is because the force needed in compression is higher than the force needed during Tension. The higher the force in compression leads to increase in the area therefore for the same scale of stress the there is more stress on the Engineering curve making it higher than the actual curve.
<em>Hence the condition of : on the same scale for stress, the tensile true stress-true strain curve is higher than the engineering stress-engineering strain curve.</em><em> </em>does not hold for compression test