Description : Untuned viscous damper ( houdaille Damper) is used with variable speed machine being control by ratio can be given by A) (damper inertia) / (main system inertia) B) (main system inertia) / (damper inertia) ... X damper inertia) / (main system inertia) D) (2 X main system inertia) / (damper inertia)
Last Answer : A) (damper inertia) / (main system inertia)
Description : According to the untuned dry fraction damper amplitude reduction will be A) Lesser if lesser amount of energy dissipated B) Greater if greater amount of energy dissipated C) Greater if lesser amount of energy dissipated D) Lesser if greater amount of energy dissipated
Last Answer : B) Greater if greater amount of energy dissipated
Description : When ≠ , the absorber is known as A. Untuned vibration absorber B. Tuned vibration absorber C. Both of above D. None of these
Last Answer : A. Untuned vibration absorber
Description : When = , the absorber is known as A. Untuned vibration absorber B. Tuned vibration absorber C. Both of above D. None of these
Last Answer : B. Tuned vibration absorber
Description : When a periodic disturbing force is applied to a machine, the force is transmitted to the ___________ by the means of spring. (A) dampers (B) foundation (C) mass (D) none of the above
Last Answer : (B) foundation
Description : In Fullarton Tachometer, a thin strip with a ______ is attached at one of its ends. (A) mass (B) spring (C) damper (D) shaft
Last Answer : (A) mass
Description : A vehicle suspension system consists of a spring and a damper. Stiffness of spring is 3.5 KN/m and damping constant of damper is 400Ns/m. If mass is 50 kg, then damping factor is A 0.606 B 0.10 C 0.666 D 0.471
Last Answer : D 0.471
Description : Determine the viscous damping coefficient if damper offers resistance 0.05N at constant velocity 0.04m/sec A 0.8N-sec/m B 1.5N-sec/m C 2.5N-sec/m D 1.25N-sec/m
Last Answer : D 1.25N-sec/m
Description : If the damper is not provided and the system is in resonance, which of the following is the correct isolation factor? A. 0B. 1/2 C. 1/4 D. Infinity
Last Answer : D. Infinity
Description : Calculate coefficient of viscous damper, if the system is critically damped. Consider the following data: 1. Mass of spring mass damper system = 350 kg 2. Static deflection = 2 x 10 -3 m 3. Natural frequency of the system = 60 rad/sec ... /m B. 80 x 10 3 N-s/m C. 42 x 10 3 N-s/m D. None of the above
Last Answer : C. 42 x 10 3 N-s/m
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 : If the damper is not provided and the system is in resonance, which of the following is the correct isolation factor? A. 0 B. 0.5 C. 0.25 D. Infinite
Last Answer : D. Infinite
Description : A vehicle suspension system consists of a spring and a damper. The stiffness of the spring is 3.6 kN/m and the damping constant of the damper is 400 Ns/m. If the mass is 50 kg, then the damping factor (d ) and damped natural ... , are a) 0.471 and 1.19 Hz b) 0.471 and 7.48 Hz c) 0.666 and 1.35 Hz
Last Answer : a) 0.471 and 1.19 Hz
Description : Calculate coefficient of viscous damper, if the system is critically damped. Consider the following data: 1. Mass of spring mass damper system = 350 kg 2. Static deflection = 2 x 10 -3 m 3. Natural frequency of the system = 60 rad/sec ... /m b. 80 x 10 3 N-s/m c. 42 x 10 3 N-s/m d. None of the above
Last Answer : c. 42 x 10 3 N-s/m
Description : If the damper is not provided and the system is in resonance, which of the following is the correct isolation factor?(A) 0 (B) 0.5 (C) 0.25 (D) Infinite
Last Answer : (D) Infinite
Description : If the damper is not provided and the system is in resonance, which of the following is the correct isolation factor? a) 0 b) 1/2 c) 1/4 d) Infinity
Last Answer : d) Infinity
Description : A vehicle suspension system consists of a spring and a damper. The stiffness of the spring is 3.6 kN/m and the damping constant of the damper is 400 Ns/m. If the mass is 50 kg, then the damping factor (d ) and damped natural ... .19 Hz b) 0.471 and 7.48 Hz c) 0.666 and 1.35 Hz d) 0.666 and 8.50 Hz
Description : The motion of a system executing harmonic motion with one natural frequency is known as _______ A. principal mode of vibration B. natural mode of vibration C. both a. and b. D. none of the above
Last Answer : C. both a. and b.
Description : The motion of a system executing harmonic motion with one natural frequency is known as _______ A) principal mode of vibration B) natural mode of vibration C) both a. and b. D)none of the above
Last Answer : C) both a. and b.
Description : In which type of vibrations, amplitude of vibration goes on decreasing every cycle? A) Damped vibrations B) Undamped vibrations C) Both a. and b. D) None of the above
Last Answer : A) Damped vibrations
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 which type of vibrations, amplitude of vibration goes on decreasing every cycle? a. Damped vibrations b. Undamped vibrations c. Both a. and b. d. None of the above
Last Answer : a. Damped vibrations
Description : In damped vibrations, the amplitude of the resulting vibration gradually reduces. This is due to the reason that an amount of energy is always dissipated to overcome the ________ * 1 point (A) Frictional resistance (B) Work done(C) Fluid pressure (D) Air pressure
Last Answer : (A) Frictional resistance
Description : The vibration in a vehicle is normally expressed in the terms of the ______________. (A) displacement (B) velocity (C) acceleration (D) none of the above
Last Answer : (C) acceleration
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 : The accelerometers are commonly used in vibration measurement due to their ___________. (A) small size and low sensitivity (B) the large size and high sensitivity (C) the large size and low sensitivity (D) small size and high sensitivity
Last Answer : (D) small size and high sensitivity
Description : Which of the following systems produce a vibration in the foundation? (A) Coupled machine(B) Uncoupled machine (C) Balanced machine (D) Unbalanced machine
Last Answer : (D) Unbalanced machine
Description : From the following, which one is a type of vibration measuring instrument? A Mechanical B Electrical C Magnetic D All of the above
Last Answer : D All of the above
Description : In vibration isolation system, if ω/ωn, then the phase difference between the transmitted force and the disturbing force is A 0° B 90° C 180° D 270°
Last Answer : C 180°
Description : The accelerometer is used as a transducer to measure earthquake in Richter scale. Its design is based on the principle that A Its natural frequency is very low in comparison to the frequency ... is equal to the frequency of vibration D Measurement of vibratory motion is without any reference point
Last Answer : C Its natural frequency is equal to the frequency of vibration
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 : 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 : When there is a reduction in amplitude over every cycle of vibration, then the body is said to have A Free vibration B Forced vibration C Damped vibration D None of the mentioned
Last Answer : C Damped vibration
Description : Calculate natural frequency of damped vibration, if damping factor is 0.52 and natural frequency of the system is 30 rad/sec which consists of machine supported on springs and dashpots. A 25.62 rad/sec B 20.78 rad/sec C 14.4 rad/sec D 15.33 rad/sec
Last Answer : A 25.62 rad/sec
Description : Which of the following is a type of free vibration? A Longitudinal vibrations B Transverse vibrations C Torsional vibrations D A, B and C
Last Answer : D A, B and C
Description : The number of cycles described in one second is known as _______. A period of vibration B cycle C frequency D all of the above
Last Answer : C frequency
Description : The motion completed during one time period is known as _______. A period of vibration B cycle C frequency D all of the above
Last Answer : B cycle
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 : What is meant by node point? A. The point at which amplitude of vibration is maximum B. The point at which amplitude of vibration is minimum C. The point at which amplitude of vibration is zero D. None of the above
Last Answer : C. The point at which amplitude of vibration is zero
Description : In a dynamic vibration absorber system, under tuned conditions which of the following relation holds good? A K 1 K 2 =M 1 M 2 B K 1 M 2 =M 1 K 2 C K 1 M 1 = K 2 M 2 D none of the mentioned
Last Answer : B K 1 M 2 =M 1 K 2
Description : Dynamic vibration absorber is suitable for A varying speed machines B constant speed machines C Zero speed range machines D None of the mentioned
Last Answer : B constant speed machines
Description : Calculate natural frequency of damped vibration, if damping factor is 0.52 and natural frequency of the system is 30 rad/sec which consists of machine supported on springs and dashpots. A 21 rad/sec B 25.62 rad/sec C 20.22 Hz D 3.15 Hz
Last Answer : B 25.62 rad/sec
Description : During resonance A the Vibrations remains unaffected B no vibration occurs C low amplitude of vibration occurs D high amplitude of vibration occurs
Last Answer : D high amplitude of vibration occurs
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 : In coulomb damping the frequency of damped vibrations is A Equal to that of undamped vibrations B Less than that of undamped vibrationsC More than that of undamped vibrations D Independent of the frequency of undamped vibration
Last Answer : A Equal to that of undamped vibrations
Description : Natural frequency of the system is due to A Resonance B Forced Vibration C Damping D Free Vibration
Last Answer : D Free Vibration
Description : Increasing which of the following factor would result in increase of free torsional vibration? A. Radius of gyration B. Mass moment of inertia C. Polar moment of inertia D. Length
Last Answer : C. Polar moment of inertia
Description : In vibration isolation system, if ω/ω n > 1, then the phase difference between the transmitted force and the disturbing force is A. 0° B. 90° C. 180° D. 270°
Last Answer : C. 180°