Strain MCQ – Strength of Materials

21. A rod of length L = 500 mm and cross-sectional area A= 60mm² is made of an elasto-plastic material having a modulus of elasticity E = 200 GPa in its elastic range and yield point σy = 300 MPa. The rod is subjected to an axial load until it is stretched 7 mm and the load is then removed. What is the resulting permanent strain?

1. 6.50 mm
2. 6.25 mm
3. 5.95 mm
4. 6.00 mm

22. During strain hardening

1. Material undergoes changes in atomic and crystalline structures
2. Increased resistance to further deformation
3. Stress strain diagram has positive slope
4. All of the above

23. Volumetric strain is defined as which of the following

1. δV/V
2. V/δV
3. m/δV
4. δV/m

24. Strain in a direction at right angles to the direction of applied force is known as

1. shear strain
2. lateral strain
3. longitudinal strain
4. volumetric strain

25. To measure _________ strain, strain rosettes are used.

1. linear
2. shear
3. volumetric
4. any of the above