## Friday, April 17, 2009

### question-2

31.Define stiffness matrix.
32.Explain stiffness matrix and its special features.
33.determine the stiffness matrix for
(a)bar element
(b)truss element
(c)Beam element neglecting axial deformation.
34.Briefly explain the various attempts made to reduce memory requirement in storing stiffness matrix.
35.State the purpose of co-ordinate transformation matrix?
36.Mention the classification of elements based on the shapes?
37.Explain the terms:
(a)CST
(b)LST
(c)QST
38.Explain the term Continuity.
39.Explain the following terms: Nodes, Primary nodes, Secondary nodes and Internal nods.
40.Distinguish between higher order elements and lower order elements.
42.Draw at least two Lagrange family rectangular elements.
43.Draw at least two Serendipity family rectangular elements.
44.Explain the LaGrange family of elements.
45.Explain the Serendipity family of elements.
46.Distinguish between LaGrange and Serendipity family of elements.
47.Draw the Pascal’s triangle for selection of interpolation polynomials.
48.Select a suitable polynomial with nine terms.
49.Define: Interpolation Function.
50.Classify the elements based on order of interpolation polynomials.
51.What are the polynomials preferred as the interpolation function.
52.Distinguish between Complex and Multiplex elements.
53.Mention the behavior of elements used for stress analysis.
54.Define: aspect ratio of an element.
55.State the significance of element distortion.
56.More element distortion is permitted in higher order element then the lower order element. Comment on the statement.
57.What is the ideal aspect ratio value for plane elements?
58.Mention the different methods of quantifying the element distortion.
59.Write short notes on: (a) selection of elements. (b) Element size and numbering.
60.Define: shape function.
61.State the requirement for a shape function.
62.what are the properties of shape functions
63.State and explain the convergence requirement of polynomial shape function.
64.Why are the polynomials preferred for shape function in FEM.?
65.What is axis symmetric element?

### interview questions

1. Define: finite element method.
2. Finite element method is an approximate method (true/false). Also justify your answer.
3. What are approximating functions?
4. What are field variables?
5. Name at least four FEA popular packages.
6. Define: i. node ii. Element.
7. Briefly explain the application of FEA for a stress analysis with an element.
8. Compare between FEM and classical methods.
9. Compare between FEM and FDM.
10. When there are several FEA packages are available in that any need to study this method.
12. Explain the concept of FEM briefly and outline the procedure.
13. Write the equation of equilibrium in plane stress condition.
14. Draw a typical three dimensional element and indicate state of stress in their positive signs.
15. Derive the equation of equilibrium in case of a two dimensional stress system.
16. State and explain generalized hook’s law.
17. Explain the term plane stress.
18. Explain the term plane strain.
19. Distinguish between plane stress and plane strain.
20. When do you select plane stress / plane strain approximation?
21. Write the constitutive equation for the plane stress and plane strain problems.
22. Write the standard form of finite element equation.
23. Draw bar element and write the stiffness matrix.
24. Define DOF.
25. Draw a plane truss element and indicate the truss element.
26. What are natural coordinates?
27. Define: local coordinates.
28. Write the stiffness matrix for the plane truss element.
29. Explain the use of element connectivity table.
30. State the purpose of element connectivity table.