Class 11 Physics — Chapter 9: Mechanical Properties of Solids Online Test

1. A material initially stressed to shows a stress of after 100 s at constant strain. What is the relaxation time ?

2. A boiler tube operates under stress of at . If the creep rate follows Norton’s law , what happens if stress doubles?

3. In an S–N curve (stress vs. number of cycles), what does the horizontal region represent?

4. In which of the following processes is strain hardening most beneficial?

5. Plastic deformation is accompanied by which atomic process?

6. For submarine hull design, which modulus is most relevant?

7. A material has Young’s modulus and bulk modulus . Find Poisson’s ratio .

8. A wire of length , area , elongates by under a load of . Find Young’s modulus.

9. A wire of length and area is stretched with stress of . If , calculate elongation.

10. What type of deformation occurs in the yield region?

11. Which industrial test uses Hooke’s law principle to check stiffness of materials?

12. A copper wire of length and cross-sectional area is subjected to a tensile force of . If , what is the elongation?

13. Which graph best represents the equation ?

14. The stress–strain graph in Hooke’s law region is:

15. A wire of length and cross-sectional area elongates by under a force of . What is the stress and strain?

16. Plasticity in solids refers to:

17. Which property is most important for designing wires used in electrical transmission?

18. Which of the following is an example of a linear elastic material?

19. A wire of length and area is subjected to a tensile force of . If its elongation is , what is the Young’s modulus of the material?

20. A steel wire of length and radius is subjected to a tensile force of . If Young’s modulus of steel is , what is the elongation of the wire?

1. Which method is generally used to measure shear modulus of a wire?

2. Which modulus determines the ability of a material to resist shape changes when used in machinery components?

3. A steel wire of length and radius is subjected to a tensile force of . If Young’s modulus of steel is , what is the elongation of the wire?

4. What branch of physics does the chapter "Mechanical Properties of Solids" mainly deal with?

5. Which application uses controlled plastic deformation of metals?

6. Which mechanical property is most crucial in designing aircraft bodies?

7. Why is plastic deformation important in the process of metal forming?

8. In the equation , what does represent?

9. Which type of materials typically show strain hardening?

10. Which factor significantly accelerates stress relaxation in metals?

11. Which of the following best represents non-linear elastic behavior?

12. What type of deformation occurs in the yield region?

13. At which point on the stress–strain curve does the material bear the maximum stress?

14. How does increasing temperature generally affect plastic deformation in metals?

15. Which application of plastic deformation is observed in earthquake-resistant building design?

16. At the breaking point, how does the material behaviour differ from plastic deformation?

17. What is strain hardening?

18. Which property of a material is most directly measured using Hooke’s law in a tensile test?

19. Which mechanical property is most important in making automobile tires?

20. What happens to dislocation density during cold working?

21. Bulk modulus can be measured experimentally by studying:

22. Which property is most desirable in making kitchen utensils?

23. How does grain size affect creep resistance at high temperatures?

24. Which modulus of elasticity is most relevant for bones under compressive loads?

25. A rod of length , area , and Young’s modulus is stretched by . Calculate the applied force.

26. What is non-linear elastic deformation?

27. A copper wire elongates by when a force of is applied. If length = , area = , find Young’s modulus.

28. Which real-life application is based directly on Hooke’s law formulation?

29. Why does a material fail at the breaking point?

30. At the elastic limit, which of the following is true?

1. Why is silicone rubber used in making prosthetic limbs?

2. Why is knowledge of plastic deformation essential in engineering design?

3. How does the rate of loading affect plastic deformation?

4. Which modulus is related to compressibility of a material?

5. A steel wire of area fractures under a maximum load of . What is the breaking stress?

6. Which modulus is most relevant for describing elasticity in solids under torsion?

7. A copper wire and a steel wire of equal length and area are joined in parallel and subjected to a load of . If , ratio of extensions (steel:copper) is:

8. A turbine blade operates at . If the activation energy for creep is , and gas constant , what factor reduces creep rate when temperature drops to ?

9. What does the area under the stress–strain curve represent?

10. At high strain rates, metals tend to:

11. Which of the following correctly represents the condition for linear elasticity?

12. Which equation represents stress relaxation behavior in viscoelastic materials (Maxwell model)?

13. In the elastic region, the slope of the stress–strain curve is equal to:

14. A boiler tube operates under stress of at . If the creep rate follows Norton’s law , what happens if stress doubles?

15. A wire of length and diameter is stretched under a load of . If the lateral strain is and longitudinal strain is , calculate Poisson’s ratio.

16. Which of the following construction materials is most elastic in terms of modulus of elasticity?

17. Which modulus plays the most important role in designing pressure cookers?

18. A beam of length , breadth , depth , is supported at ends and loaded at the center with . Find central deflection. ()

19. Which relation connects Young’s modulus , bulk modulus , and Poisson’s ratio ?

20. For the above material (Q542), calculate bulk modulus .

21. In non-linear elastic deformation, which of the following is true?

22. For submarine hull design, which modulus is most relevant?

23. What does Young’s modulus measure?

24. Why is elasticity important in stents used to open blocked arteries?

25. What is the correct definition of elasticity in solids?

26. In material testing, why is it crucial to know the breaking point of a solid?

27. Which of the following is the primary cause of brittle fracture in materials?

28. Which property of solids explains why railway tracks have gaps left between them?

29. Which modulus is critical in designing dies and molds for shaping materials?

30. In material testing, stress relaxation helps to determine:

31. Which property of materials is utilized in the design of trampolines?

32. At which point on the stress–strain curve does the material bear the maximum stress?

33. A material that is both malleable and ductile is:

34. How does knowledge of mechanical properties help in sports equipment design?

35. Which factor causes metals to become brittle at low temperatures?

36. In biomechanics, tendons and ligaments are modeled as:

37. Which of the following statements best distinguishes proportionality limit and elastic limit?

38. A wire of length is stretched by a load of . The energy stored per unit volume is . Find Young’s modulus if cross-sectional area = .

39. How does increasing temperature generally affect plastic deformation in metals?

40. Which of the following equations estimates the stress intensity factor for fracture mechanics?

41. What does a higher value of Young’s modulus imply about a material?

42. The proportionality limit corresponds to which part of the stress–strain curve?

43. Which of the following materials shows a very well-defined yield point?

44. In forging metals, which type of deformation is primarily involved?

45. In torsional testing, the analog of Hooke’s law relates:

46. A wire of length and diameter is subjected to a load of . If Young’s modulus = , find the strain energy per unit volume.

47. Which physical property of solids is determined directly from Hooke’s law equation ?

48. In the plastic deformation region, what is true about stress and strain?

49. Plastic deformation is accompanied by which atomic process?

50. A cylindrical rod of radius , length , is subjected to shear stress of . If shear modulus , find the lateral displacement of top face.