![Student Name/ID ____________________________________________
Question 1
An unconstrained 3-D frame with 4 nodes has _______ frequencies number of zero
Choose one answer.
1. 3
2. 1
3. 2
4. 6
Question 2
The simultaneous linear equations used in FEM for solution of static problems are K X =F, the
methods available for solving these equations are divided into two types: direct and iterative
Choose one answer.
1. false
2. true
Question 3
A generalized Eigen value problem [ K - ω2 M] X =0 has a non-zero solution for X. What can
be the value of determinant of the matrix [K- ω2M]?
Choose one answer.
1. +1
2. any integer
3. zero
4. Positive integer
Question 4
Any time-dependent external load acting on the structure, whose frequency matches with the
_______of the structure, causes _______ and produces large displacements leading to failure
of the structure
Choose one answer.
1. frequency, resonance
2. forced frequency, resonance
3. natural frequency, resonance
4. natural frequency, mode shape
Question 5
Identify the correct name of [M] from equation <img src="@@PLUGINFILE@@/Dy analysis
1.jpg" />
Choose one answer.
1. Consistent mass matrix
2. mass matrix of the element
3. stiffness matrix of the element
4. Lumped mass matrix
Question 6
Characteristic equation of dynamic equation given in figure takes a form <img
src="@@PLUGINFILE@@/Dy analysis 1.jpg" />
Choose one answer.
1. [A] - λ = 0
2. [A] - λ [I] = 0
3. [A] - [I] = 0
4. [A] - λ [I]
Page 1](https://image.slidesharecdn.com/unit6dynamicanalysisbl1-211005115530/85/Unit-6-dynamic-analysis-bl-1-1-320.jpg)
![Question 7
Mass, being a _______ quantity has _______ effect along the three translational degrees of
freedom and is not shared
Choose one answer.
1. Scalar, different
2. Scalar, Same
3. Vector, different
4. Vector, same
Question 8
Mass, being a scalar quantity, is not influenced by the _______ coordinate system so that no
transformation matrix is required for mass.
Choose one answer.
1. Local or Global
2. Local
3. Global
4. None of the above
Question 9
Total mass of the element is assumed equally distributed at all the nodes of the element in
each of the translational degrees of freedom. The approch is known as
Choose one answer.
1. Consistent and Lumped Mass
2. Consistent mass
3. Lumped mass
4. None of the above
Question 10
Off-diagonal elements of mass matrix are all zero. It is a characteristic of which mass matrix
approach?
Choose one answer.
1. Centrifugal Mass
2. Consistent Mass
3. Lumped Mass
4. Concentrated Mass
Question 11
Lumped mass matrix of truss element with 1 translational DOF per node along its local X-axis
Choose one answer.
1. ρAL [1 0 0 1]
2. ρAL [1 -1 -1 1]
3. ρAL/2 [1 -1 -1 1]
4. ρAL/2 [1 0 0 1]
Question 12
A frequency of value _______ indicates rigid body motion along one dof
Choose one answer.
1. infinity
2. zero
3. 1
4. less than zero
Page 2](https://image.slidesharecdn.com/unit6dynamicanalysisbl1-211005115530/85/Unit-6-dynamic-analysis-bl-1-2-320.jpg)
Unit 6 dynamic analysis bl 1
- 1. Student Name/ID ____________________________________________ Question 1 An unconstrained 3-D frame with 4 nodes has _______ frequencies number of zero Choose one answer. 1. 3 2. 1 3. 2 4. 6 Question 2 The simultaneous linear equations used in FEM for solution of static problems are K X =F, the methods available for solving these equations are divided into two types: direct and iterative Choose one answer. 1. false 2. true Question 3 A generalized Eigen value problem [ K - ω2 M] X =0 has a non-zero solution for X. What can be the value of determinant of the matrix [K- ω2M]? Choose one answer. 1. +1 2. any integer 3. zero 4. Positive integer Question 4 Any time-dependent external load acting on the structure, whose frequency matches with the _______of the structure, causes _______ and produces large displacements leading to failure of the structure Choose one answer. 1. frequency, resonance 2. forced frequency, resonance 3. natural frequency, resonance 4. natural frequency, mode shape Question 5 Identify the correct name of [M] from equation <img src="@@PLUGINFILE@@/Dy analysis 1.jpg" /> Choose one answer. 1. Consistent mass matrix 2. mass matrix of the element 3. stiffness matrix of the element 4. Lumped mass matrix Question 6 Characteristic equation of dynamic equation given in figure takes a form <img src="@@PLUGINFILE@@/Dy analysis 1.jpg" /> Choose one answer. 1. [A] - λ = 0 2. [A] - λ [I] = 0 3. [A] - [I] = 0 4. [A] - λ [I] Page 1
- 2. Question 7 Mass, being a _______ quantity has _______ effect along the three translational degrees of freedom and is not shared Choose one answer. 1. Scalar, different 2. Scalar, Same 3. Vector, different 4. Vector, same Question 8 Mass, being a scalar quantity, is not influenced by the _______ coordinate system so that no transformation matrix is required for mass. Choose one answer. 1. Local or Global 2. Local 3. Global 4. None of the above Question 9 Total mass of the element is assumed equally distributed at all the nodes of the element in each of the translational degrees of freedom. The approch is known as Choose one answer. 1. Consistent and Lumped Mass 2. Consistent mass 3. Lumped mass 4. None of the above Question 10 Off-diagonal elements of mass matrix are all zero. It is a characteristic of which mass matrix approach? Choose one answer. 1. Centrifugal Mass 2. Consistent Mass 3. Lumped Mass 4. Concentrated Mass Question 11 Lumped mass matrix of truss element with 1 translational DOF per node along its local X-axis Choose one answer. 1. ρAL [1 0 0 1] 2. ρAL [1 -1 -1 1] 3. ρAL/2 [1 -1 -1 1] 4. ρAL/2 [1 0 0 1] Question 12 A frequency of value _______ indicates rigid body motion along one dof Choose one answer. 1. infinity 2. zero 3. 1 4. less than zero Page 2
- 3. Question 13 Identify the type of element for which following lumped mass matrix is used <img src="@@PLUGINFILE@@/Dy analysis2.jpg" /> Choose one answer. 1. CST element 2. Bar Element 3. Truss Element 4. Beam Element Question 14 Identify the type of element for which following lumped mass matrix is used <img src="@@PLUGINFILE@@/Dy analysis 3.jpg" /> Choose one answer. 1. Beam Element 2. Bar Element 3. Truss Element 4. CST Element Question 15 What should be correct fill in the box <img src="@@PLUGINFILE@@/Dy analysis 4.jpg" /> Choose one answer. 1. 3 2. 1 3. 2 4. 4 Question 16 Element mass matrix is _______ with the assumed displacement field or element stiffness matrix Choose one answer. 1. Consistent 2. Inconsistent 3. similar 4. dissimilar Question 17 In consistent mass approach, the interpolation functions are _______ which are used for approximating displacement field over the element Choose one answer. 1. Different 2. Similar 3. Same 4. equivalent Question 18 Select the correct type of element and type of mass matrix for the following figure <img src="@@PLUGINFILE@@/Dy analysis 5.jpg" /> Choose one answer. 1. Bar element and Lumped Mass Matrix 2. Bar element and Consistent Mass Matrix 3. Truss element and Consistent Mass Matrix 4. Truss element and Lumped Mass Matrix Page 3
- 4. Question 19 Following is the _______ matrix for _______ type of element <img src="@@PLUGINFILE@@/Dy analysis 6.jpg" /> Choose one answer. 1. Consistent Mass and Truss Element 2. Lumped Mass and Beam Element 3. Lumped Mass and CST Element 4. Consistent Mass and Beam Element Question 20 Natural frequencies obtained using lumped mass matrix are _______ than exact values Choose one answer. 1. SAME 2. HIGHER 3. LOWER 4. DIFFERENT Question 21 Consistent mass matrix yields _______ results but with _______ computational cost Choose one answer. 1. more accurate, less 2. less accurate, less 3. more accurate, more 4. less accurate, more Question 22 Consistent mass matrix is banded matrix of the _______ order as that for the stiffness matrix Choose one answer. 1. Different 2. Less 3. More 4. Same Question 23 With lumped mass matrix, the differential equation of vibration refers to Choose one answer. 1. mode superposition 2. elastic coupling 3. inertia coupling 4. both inertia and elastic coupling Question 24 Natural frequencies obtained with lumped mass matrices are _______ than those obtained with consistent mass matrices, while the mode shapes are practically _______. Choose one answer. 1. LOWER, SAME 2. HIGHER, SAME 3. SAME, SAME 4. LOWER, DIFFERENT Question 25 With consistent mass matrix, the differential equation of vibration refers to Choose one answer. 1. mode superposition 2. elastic coupling 3. inertia coupling 4. both inertia and elastic coupling Page 4
- 5. Question 26 Normalising eigenvector w.r.t. mass matrix is useful in Choose one answer. 1. frequency response 2. mode superposition 3. evaluating natural frequencies 4. damped vibrations Question 27 A 4 - noded cantilever gives _______ number of frequencies Choose one answer. 1. 6 2. 3 3. 4 4. 9 Question 28 A natural mode of vibration represents _______ at each node Choose one answer. 1. proportional displacements 2. absolute displacements 3. relative displacements 4. absolute strain Question 29 If a solid body is deformed elastically and suddenly released, it tends to vibrate about _______ position Choose one answer. 1. Equilibrium 2. Centre of mass 3. Axis 4. Neutral Axis Question 30 The equation of motion for damped vibration is given by Choose one answer. 1. c x + K x = 0 2. m x +c x + K x = 0 3. m x + c x = 0 4. None of the above Page 5