Description : n which direction does the accelerating force acts? a) Opposite to the motion b) Along the motion c) Perpendicular to motion d) Variable
Last Answer : b) Along the motion
Description : Which of the following statements are TRUE for damped vibrations? (P) . For a system having critical damping, the value of the damping ratio is unity and system does not undergo a vibratory motion. (Q) . Logarithmic decrement method ... Q only (B) P and S only (C) P, Q and R only (D) Q and S only
Last Answer : (C) P, Q and R only
Description : Which of the following statements is/are true for coulomb damping? 1. Coulomb damping occurs due to friction between two lubricated surfaces2. Damping force is opposite to the direction of motion of vibrating body ... 2, 3 and statement 4 c. Only statement 2 d. All the above statements are true
Last Answer : c. Only statement 2
Description : The damping is used to control the __________ of body. A. Force B. Viscosity C. Motion D. None
Last Answer : C. Motion
Description : What is meant by critical damping coefficient? * 1 point (A) Frequency of damped free vibrations is less than zero (B). The motion is a periodic in nature (C). Both a. and b. (D). None of the above
Last Answer : (C). Both a. and b.
Description : What is meant by critical damping coefficient? A Frequency of damped free vibrations is less than zero B The motion is aperiodic in nature C Both a. and b. D None of the above
Last Answer : B The motion is aperiodic in nature
Description : The equation of motion for a vibrating system with viscous damping is d 2 x/dt 2 + c/m X dx/dt + s/m X x = 0 If the roots of this equation are real, then the system will be A. over damped B. under damped C. critically damped D. none of the mentioned
Last Answer : A. over damped
Description : If frequency of excitation of a forced vibration system with negligible damping is very close to natural frequency of the system, then the system will A) Execute harmonic motion of large amplitude B) Beat with a very high peak amplitude C) Perform aperiodic motion D) None of the above
Last Answer : A) Execute harmonic motion of large amplitude
Description : What is meant by critical damping coefficient? B ( A )Frequency of damped free vibrations is less than zero ( B )The motion is aperiodic in nature ( C )Both a. and b. (D)None of the above
Last Answer : ( B )The motion is aperiodic in nature
Description : In coulomb damping, the amplitude of motion in each cycle is reduced by A. F/K B. 2F/K C. 4F/K D. F/4K
Last Answer : C. 4F/K
Description : The motion of particle is represented by, x = Asin(wt) in which A stands for A. Amplitude B. Wavelength C. Frequency D. Damping
Last Answer : A. Amplitude
Description : What is meant by critical damping coefficient? a. Frequency of damped free vibrations is less than zero b. The motion is aperiodic in nature c. Both a. and b. d. None of the above
Last Answer : b. The motion is aperiodic in nature
Description : The equation of motion for a vibrating system with viscous damping is d 2 x/dt 2 + c/m X dx/dt + k/m X x = 0 If the roots of this equation are real, then the system will be a) over damped b) under damped c) critically damped d) none of the mentioned Ans:a
Last Answer : a) over damped
Description : If harmonic motion of same frequency and same phase are superimposed in two perpendicular directions ( x and y) then, the resultant motion will be, A) circle B) An ellipse C) An square D) An rectangle
Last Answer : C) An square
Description : Which of the following is a type of transmitted force to the foundation? (A) Damping force (B) Undamping force (C) Tensile force (D) Torsional force
Last Answer : (A) Damping force
Description : The ratio of the maximum displacement of the forced vibration to the deflection due to the static force, is known as A Damping factor B Damping coefficient C Logarithmic decrement D Magnification factor
Last Answer : D Magnification factor
Description : In a spring-mass system, which of the following force is not considered? A Spring force B Damping force C Accelerating force D A and B
Last Answer : B Damping force
Description : The ratio of the maximum displacement of the forced vibration to the deflection due to the static force is known as A Logarithmic decrement B Magnification factor C Damping factor D None of the mentioned
Last Answer : B Magnification factor
Description : The angle between spring force and damping force is A 180 0 B 120 0 C 90 0 D 0 0
Last Answer : C 90 0
Description : Which of the following is true regarding Ɛ>1? A. Transmitted force is greater than applied force B. Transmitted force is less than applied force C. Spring force is less than applied force D. Damping force is less than applied force
Last Answer : A. Transmitted force is greater than applied force
Description : Calculate damped natural frequency, if a spring mass damper system is subjected to periodic disturbing force of 30 N. Damping coefficient is equal to 0.76 times of critical damping coefficient and undamped natural frequency is 5 rad/sec A. 3.99 rad/sec B. 2.13 rad/sec C. 4.12 rad/sec D. 3.24 rad/sec
Last Answer : D. 3.24 rad/sec
Description : Which of the following relations is true for viscous damping? A) Force α relative displacement B) Force α relative velocity C) Force α (1 / relative velocity) D) None of the above
Last Answer : B) Force α relative velocity
Description : In a spring-mass system, which of the following force is not considered? B ( A ) Spring force ( B ) Damping force ( C ) Accelerating force ( D ) A and B
Last Answer : B ) Damping force
Description : The ratio of maximum displacement of the forced vibration to the deflection due to the static force, is known as A. Damping FactorB. Damping Coefficient C. Logarithmic Decrement D. Magnification Factor
Last Answer : D. Magnification Factor
Description : The angle between spring force and damping force is A. 180 0 B. 90 0 C. 0 0 D. None of the above
Last Answer : B. 90 0
Description : Which of the following relations is true for viscous damping? a. Force α relative displacement b. Force α relative velocity c. Force α (1 / relative velocity) d. None of the above
Last Answer : b. Force α relative velocity
Description : The ratio of the maximum displacement of the forced vibration to the deflection due to the static force, is known as a) Damping factor b) Damping coefficient c) Logarithmic decrement d) Magnification factor
Last Answer : d) Magnification factor
Description : Reduction in vibration amplitude after one complete cycle of single degree free vibration with dry friction damping is_____, if where F"= frictional force between mass and surface and k =stiffness of the system. a)4F/k a b) 2f/K C) 3F/k D)8F/k
Last Answer : a)4F/k
Description : The ratio of the maximum displacement of the forced vibration to the deflection due to the static force is known as (A) damping factor (B) damping coefficient (C) logarithmic decrement (D) magnification factor
Last Answer : (D) magnification factor
Description : Which of the following is true regarding Ɛ>1? a) Transmitted force is greater than applied force b) Transmitted force is less than applied force c) Spring force is less than applied force d) Damping force is less than applied forc
Last Answer : a) Transmitted force is greater than applied force
Description : Which of the following is a type of transmitted force to the foundation? a) Damping force b) Undamping force c) Tensile force d) Torsional force
Last Answer : a) Damping force
Description : The ratio of the maximum displacement of the forced vibration to the deflection due to the static force, is known as a) damping factor b) damping coefficient c) logarithmic decrement d) magnification factor
Last Answer : d) magnification factor
Description : Force acts in a direction opposite to the di- rection of motion is?
Last Answer : Static friction
Description : A vibrating machine of 100 kg is mounted on a rubber pad which has stiffness of 500 N/m. Determine force transmitted to the foundation if the unbalanced force 500 N acts on it. The frequency ratio (ω/ω n ) is 1.5 and ξ = 0.5 A. 461.62 N B. 400.23 N C. 450 N D. Insufficient data
Last Answer : A. 461.62 N
Description : In a solid arch, shear force acts (A) Vertically upwards (B) Along the axis of the arch (C) Perpendicular to the axis of arch (D) Tangentially to the arch
Last Answer : (C) Perpendicular to the axis of arch
Description : The equation of motion for spring mass system includes A. Inertia Force B. Spring Force C. Both D. Gravitational force
Last Answer : C. Both
Description : In a two-rotor system, torsional vibration occurs only if the rotors are moving in the ______ direction. (A) same (B) opposite (C) either same or opposite (D) none of the above
Last Answer : (B) opposite
Description : In a two-rotor system, torsional vibration occurs only if the rotors are moving in the ______ direction. A. same B. opposite C. either same or opposite D. none of the above
Last Answer : B. opposite
Description : In the diagram shown below, if rotor X and rotor Z rotate in same direction and rotor Y rotates in opposite direction, then specify the type of node vibration. A. Three node vibration B. Two node vibration C. Single node vibration D. None of the above
Last Answer : B. Two node vibration
Description : Which of the following statements is/are true? A. Torsional vibrations do not occur in a three rotor system, if rotors rotate in same direction B. Shaft vibrates with maximum frequency when rotors ... C. Zero node behavior is observed in rotors rotating in opposite direction D. All of the above
Last Answer : A. Torsional vibrations do not occur in a three rotor system, if rotors rotate in same direction
Description : Which of the following statements is/are true? A) Torsional vibrations do not occur in a three rotor system, if rotors rotate in same direction B) Shaft vibrates with maximum frequency when rotors ... C) Zero node behavior is observed in rotors rotating in opposite direction D) All of the above
Last Answer : A) Torsional vibrations do not occur in a three rotor system, if rotors rotate in same direction
Description : When heavy rotating masses are connected by a shaft and equal and opposite torques are applied to these masses (rotors) A. The rotors vibrate torsionally in the same direction. B. The rotors vibrate torsionally ... on the axis of shaft which remains undisturbed by vibration. D. Both (B) and (C)
Last Answer : D. Both (B) and (C)
Description : In the diagram shown below, if rotor X and rotor Z rotate in same direction and rotor Y rotates in opposite direction, then specify the no of degree of freedom vibration.a. Three degree of freedom vibration b. Two degree of freedom vibration c. Single degree of freedom vibration d. None of the above
Last Answer : b. Two degree of freedom vibration
Description : Which of the following statements is/are true? a. Torsional vibrations do not occur in a three rotor system, if rotors rotate in same direction b. Shaft vibrates with maximum frequency when rotors ... c. Zero node behavior is observed in rotors rotating in opposite direction d. All of the above
Last Answer : a. Torsional vibrations do not occur in a three rotor system, if rotors rotate in same direction
Description : Unit of the damping factor is ______. (A) Nm/s (B) N/sm (C) N/m (D) none of the above
Last Answer : (D) none of the above
Description : In vibration isolation system, if ω/ωn < 2, then for all values of damping factor, the transmissibility will be A less than unity B equal to unity C greater than unity D zero
Last Answer : C greater than unity
Description : In steady state forced vibrations, the amplitude of vibrations at resonance is _____________ damping coefficient. A equal to B directly proportional to C inversely proportional to D independent of
Last Answer : C inversely proportional to
Description : A simple pendulum is found to vibrate at a frequency of 0.5Hz in vacuum and0.45 Hz in a viscous fluid medium. Find the damping factor. 0.5122 (B) 0.9272 (C) 0.4359 (D) 0.2568
Last Answer : (C) 0.4359