Description : A simple pendulum is found to vibrate at a frequency of 0.5Hz in vacuum and 0.45Hz in a viscous fluid medium. Find the damping factor. A 0.5122 B 0.9237 C 0.4359 D 0.2568
Last Answer : C 0.4359
Description : When a system vibrates in a fluid medium, the damping is (a) viscous (b) Coulomb (c) solid
Last Answer : (a) viscous
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 : 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 : 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 : Fluid resistance causes damping which is known as ______ a) Resistance damping b) Fluid dampingc) Viscous damping d) Liquid damping
Last Answer : c) Viscous damping
Description : In case of viscous damping the frequency of damped vibration is A) Equal to that of undamped vibrations B) Less than that of undamped vibrations C) Greater than that of undamped vibrations D) Independent than that of undamped vibrations
Last Answer : B) Less than that of undamped vibrations
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 : 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 : 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 : Natural frequency of simple pendulum is proportional to A. Length B. Acceleration due to gravity C. Both D. None
Last Answer : B. Acceleration due to gravity
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 : Eddy current damping is an example of _____ A Coulomb damping B Hysteresis damping C Viscous damping D Dry friction damping
Last Answer : C Viscous damping
Description : The unit of the viscous damping coefficient is A N-m/sec B m/N-sec C N-sec-m D N-sec/m
Last Answer : D N-sec/m
Description : When parts of a vibrating system slide on a dry surface, the damping is A. Viscous. B. Coulomb C. Structural D. Eddy current
Last Answer : B. Coulomb
Description : Eddy current damping is an example of _____A. Coulomb damping B. Hysteresis damping C. Viscous damping D. Dry friction damping
Last Answer : C. Viscous damping
Description : Eddy current damping is an example of _____ A) Coulomb damping B) Hysteresis damping C) Viscous damping D) Dry friction damping
Last Answer : C) Viscous damping
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 equivalent viscous damping coefficient Ceq for coulomb damping is given by A) 4F/πωx B) 4πF/ωx C) πωx/4F D) ωx/4Πf
Last Answer : A) 4F/πωx
Description : The units of viscous damping coefficient is A) N-m/sec B) m/N-sec C) N-sec/m D) N-m-sec
Last Answer : C) N-sec/m
Description : Following are the types of damping A. Viscous Damping B. Coulomb Damping C. Hysteresis Damping D. All the above
Last Answer : D. All the above
Description : Eddy current damping is an example of _____ a. Coulomb damping b. Hysteresis damping c. Viscous damping d. Dry friction damping
Last Answer : c. Viscous damping
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 : 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 : Calculate natural frequency of damped vibration, if damping factor is 0.52 and A 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 : Calculate natural frequency of damped vibration, if damping factor is 0.52 and natural frequ the system is 30 rad/sec which consists of machine supported on springs and dashpots. a. 25.62 rad/secb. 20.78 rad/sec c. 14.4 rad/sec d. 15.33 rad/sec
Last Answer : a. 25.62 rad/sec
Description : At which frequency ratio, phase angle increases as damping factor increases? A. When frequency ratio is less than unity B. When frequency ratio is more than unity C. When frequency ratio is zero D. All of the above
Last Answer : A. When frequency ratio is less than unity
Description : The principal of mode vibration can be given by A) Two masses vibrate at Different frequency and in same phase B) Two masses vibrate at Different frequency and in Different phase C) Two masses vibrate at same frequency and in Different phase D) Two masses vibrate at same frequency and in same phase
Last Answer : D) Two masses vibrate at same frequency and in same phase
Description : When two masses vibrate at the same frequency and in phase, it is called a principal mode of vibration A. True B. False C. Does not depend on vibration D. None of the above
Last Answer : A. True
Description : The number of degrees of freedom of a simple pendulum is: (a) 0 (b) 1 (c) 2
Last Answer : (b) 1
Description : In semi definite system, one of the natural frequencies is found to 15 Hz. The other natural frequency will be A. 15 Hz B. 0 Hz C. 30 Hz D. None of these
Last Answer : B. 0 Hz
Description : When a rigid body is suspended vertically and it oscillates with a small amplitude under the action of the force of gravity, the body is known as * 1 point (A) simple pendulum (B) torsional pendulum (C) compound pendulum (D) second’s pendulum
Last Answer : (C) compound pendulum
Description : When a rigid body is suspended vertically and it oscillates with a small amplitude under the action of the force of gravity, the body is known as A. simple pendulum B. torsional pendulum C. compound pendulum D. second’s pendulum
Last Answer : C. compound pendulum
Description : The time period of a simple pendulum does not depend upon the mass of the body suspended at the free end of the string. This statement is known as ___________ . (A) law of gravity (B) law of mass (C) law of isochronism (D) law of length
Last Answer : (B) law of mass
Description : When a rigid body is suspended vertically and it oscillates with a small amplitude under the action of the force of gravity, the body is known as (A) simple pendulum B) torsional pendulum (C) compound pendulum (D) second’s pendulum
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 : find the value of logarithmic decrement of a vibratory system if its natural frequency is 10rad/sec, its mass is 10kg and its damping constant is 100N.s/m a) 36.27 b)362.7 c)0.3627 d)3.627
Last Answer : d)3.627
Description : . In centrifugal pendulum absorber , the natural frequency in cycle per second can be given by A Fn =N √(R/L) B Fn =1/N √(R/L) C Fn =N/2 √(R/L) D Fn =N2 √(R/L)
Last Answer : A Fn =N √(R/L)
Description : Frequency of centrifugal pendulum absorber is always proportional to A) Oscillating motion B) Transfer motion C) Speed of rotating body D) All of the above
Last Answer : C) Speed of rotating body
Description : In centrifugal pendulum absorber , the natural frequency in cycle per second can be given by A) Fn =N √(R/L) B) Fn =1/N √(R/L) C) Fn =N/2 √(R/L) D) Fn =N2 √(R/L)
Last Answer : A) Fn =N √(R/L)
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 : Calculate logarithmic decrement if damping factor is 0.33. A 1.36 B 3.23 C 5.16D 2.19
Last Answer : D 2.19
Description : A vibrating system having mass 1kg, a spring of stiffness 1000N/m and damping factor of 0.632 and it is put to harmonic excitation of 10N. Find the amplitude at resonance. A 0.079 B 7.9C 0.056 D 0.00791
Last Answer : D 0.00791
Description : Calculate logarithmic decrement if damping factor is 0.086 A 0.245 B 0.425 C 0.542 D 0.252
Last Answer : C 0.542
Description : Calculate logarithmic decrement if damping factor is 0.33. D ( A ) 1.36 ( B ) 3.23 ( C ) 5.16 ( D ) 2.19
Last Answer : D ) 2.19
Description : Calculate logarithmic decrement if damping factor is 0.33. a. 1.36 b. 3.23 c. 5.16 d. 2.19
Last Answer : d. 2.19
Description : In which of the cases the factor c = 0? a) When there is damping b) No damping c) Resonance d) c is never 0
Last Answer : b) No damping
Description : When the torsional pendulum vibrating the observed amplitudes on the same side of neutral axis for successive cycles are found to decay 50% of the initial value determine logarithmic decrement. A 0.065 B 0.006 C 0.693 D 0.5
Last Answer : C 0.693
Description : When the torsional pendulum vibrating, the observed amplitudes on the same side of the neutral axis for successive cycles are found to decay 50% of the initial value determine logarithmic decrement. A 0.065 B 0.006 C 0.693 D 0.5
Description : A 1 kg mass is suspended by a spring having a stiffness of 0.4 N/mm. Determine the natural frequency. A 20 rad/sec B 30 rad/sec C 20 Hz D 30 Hz
Last Answer : B 30 rad/sec