Description : Time taken to complete one cycle is known as A Resonance B Frequency C Period D Damping
Last Answer : C Period
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 : 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 : 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 : For an under damped harmonic oscillator, resonance A Occurs when excitation frequency is greater than undamped natural frequency B Occurs when excitation frequency is less than undamped natural frequency C Occurs when excitation frequency is equal to undamped natural frequency D Never occurs
Last Answer : C Occurs when excitation frequency is equal to undamped natural frequency
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 : In the case of steady state forced vibration at a resonance, the amplitude of vibration is A) Inversely proportional to damping coefficient B) Inversely proportional to damping ratio C) Inversely proportional to resonant frequency D) Directly proportional to resonant frequency
Last Answer : B) Inversely proportional to damping ratio
Description : Natural frequency of the system is due to A) Free vibration B) Forced vibration C) Resonance D) Damping
Last Answer : A) Free vibration
Description : Resonance is a phenomenon when the frequency of external exciting force is A) Twice the natural frequency of the system B) Half the natural frequency of the system C) Same as the natural frequency of the system D) None of the above
Last Answer : C) Same as the natural frequency of the system
Description : For an under damped harmonic oscillator, resonance a) occurs when excitation frequency is greater than undamped natural frequency b) occurs when excitation frequency is less than undamped natural frequency c) occurs when excitation frequency is equal to undamped natural frequency d) never occurs
Last Answer : c) occurs when excitation frequency is equal to undamped natural frequency
Description : For an underdamped harmonic oscillator, resonance ______. (A) occurs when excitation frequency is greater than the undamped natural frequency (B) occurs when excitation frequency is less than the ... ) occurs when excitation frequency is equal to the undamped natural frequency (D) never occurs
Last Answer : (C) occurs when excitation frequency is equal to the undamped natural frequency
Description : The instruments which are used to measure the ___________ of a vibrating body are called vibration measuring instrument. (A) displacement (B) velocity (C) acceleration (D) all of the above
Last Answer : (D) all of the above
Description : The advantage of critical damping is A. That vibrating body come to rest in smallest possible time B. There is no vibration C. That amplitude of vibration is maximum D. The amplitude of vibration is minimum
Last Answer : A. That vibrating body come to rest in smallest possible time
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 : 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 : . The motion completed during one time period is known as _______. A. period of vibration B. cycle C. frequency D. all of the above
Description : The motion completed during one time period is known as _______. B ( A ) period of vibration ( B ) cycle ( C ) frequency ( D ) all of the above
Last Answer : ( B ) cycle
Description : A seismometer is a device used to measure the ___________ of a vibrating body. (A) displacement (B) velocity (C) acceleration (D) all of the above
Last Answer : (A) displacement
Description : Which of the following instruments measure the amplitude of a vibrating body? (A) Vibrometers (B) Seismometer (C) Both (a) and (b) (D) None of these
Last Answer : (C) Both (a) and (b)
Description : Calculate logarithmic decrement if the amplitude of the vibrating body reduces to half in two cycles A 0.346 B 0.693 C 0.301 D 0.150
Last Answer : A 0.346
Description : When no external force is acting on the vibrating body, the vibrations are said to be A. Free Vibrations B. Forced Vibrations C. Loaded Vibrations D. Undamped Vibrations
Last Answer : A. Free Vibrations
Description : When the external force is acting on the vibrating body, the vibrations are said to be A. Natural Vibrations B. Forced Vibrations C. Loaded Vibrations D. Undamped Vibrations
Last Answer : B. Forced Vibrations
Description : The instrument that measures the displacement of a vibrating body is called__________ a. seismometer b. transducer c. accelerometer
Last Answer : a. seismometer
Description : The instrument that measures the acceleration of a vibrating body is called___________
Last Answer : Ans- Accelerometer
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 : Determine logarithmic decrement, if the amplitude of a vibrating body reduces to 1/6 th in tw cycles. a. 0.223 b. 0.8958 c. 0.3890 d. None of the above
Last Answer : b. 0.8958
Description : In vibrometer, the relative motion between the mass and vibrating body is converted into proportional ________. (A) current (B) voltage (C) resistance (D) ampere
Last Answer : (B) voltage
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 number of cycles described in one second is known as _______. C ( A ) period of vibration ( B ) cycle ( C ) frequency ( D ) all of the above
Last Answer : C ) frequency
Description : A resonant system has a fundamental frequency of 100 Hz. If the next higher frequency that gives a resonance are 300 Hz and 500 Hz, the system could be (a) A pip open at both ends (b) A pipe ... (c) A string vibrating between two fixed points (d) A pipe open at one end and closed at the other
Last Answer : Ans:(d)
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 : 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 : 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 : The rotating shaft or rotor vibrates with excessive lateral vibration at angular speed at which occurs is called as A) rotating speed B) critical speed C) vibrating speed D) None of the above
Last Answer : B) critical speed
Description : In under damped vibrating system, the amplitude of vibration ______. (A) decreases linearly with time (B) increases linearly with time (C) decreases exponentially with time (D) increases exponentially with time
Last Answer : (C) decreases exponentially with time
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 : In under damped vibrating system, if x 1 and x 2 are the successive values of the amplitude on the same side of the mean position, then the logarithmic decrement is equal to A x 1 /x 2 B log (x 1 /x 2 ) C loge (x 1 /x 2 ) D log (x 1 .x 2 )
Last Answer : C loge (x 1 /x 2 )
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 : Calculate the value of critical damping coefficient if a vibrating system has mass of 4kg and stiffness of 100N/m A 20 N-sec/m B 40 N-sec/m C 60 N-sec/m D 80 N-sec/m
Last Answer : B 40 N-sec/m
Description : A system is said to be critically damped if the damping factor for a vibrating system is A Zero B Less than one C One D More than one
Last Answer : C One
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 : In a 2-mass 3 spring vibrating system the two masses each are of 9.8 kg coupling spring is having a stiffness of 3430 N/m whereas the other two springs have each a stiffness of 8820 N/m. The two natural frequencies in rad /sec are A) 10 & 20 B) 20 & 30 C) 30 & 40D) 40 & 50
Last Answer : C) 30 & 40
Description : Beats phenomenon occurs when a vibrating system is subjected to two different frequencies which are A) Quite different B) Equal C) Slightly different D) Integral multiple of each other
Last Answer : C) Slightly different
Description : In under damped vibrating system, if x 1 and x 2 are the successive values of the C amplitude on the same side of the mean position, then the logarithmic decrement is equal to ( A ) x 1 /x 2 ( B ) log (x 1 /x 2 ) ( C ) loge (x 1 /x 2 ) ( D ) log (x 1 .x 2 )
Last Answer : ( C ) loge (x 1 /x 2 )
Description : The number of degrees of freedom of a vibrating system depends on a. number of masses b. number of masses and degrees of freedom of each mass c. number of coordinates used to describe the position of each mass d. None of the above
Last Answer : b. number of masses and degrees of freedom of each mass
Description : In under damped vibrating system, if x1 and x2 are the successive values of the amplitude on the same side of the mean position, then the logarithmic decrement is equal to a) x1/x2 b) log (x1/x2) c) ln (x1/x2) d) log (x1.x2)
Last Answer : c) ln (x1/x2)