For a 2nd order servo system, the damping ratio δ = 0.5456 and undamped natural frequency is ωn = 31.6 rad/sec. The percent overshoot is 14.10
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 : 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 : 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 : Given a unity feedback system with G(s)=k/s (s+4), the value of k for damping ratio of 0.5 is
Last Answer : Given a unity feedback system with G(s)=k/s (s+4), the value of k for damping ratio of 0.5 is 16
Description : What is the effect on the undamped natural frequency of a single-degree-of-freedom system if the mass of the system is increased? A The frequency will increase B The frequency will stay the same C The frequency will decrease D None of these
Last Answer : C The frequency will decrease
Description : What is the effect on the undamped natural frequency of a single-degree-of- C freedom system if the mass of the system is increased? ( A ) The frequency will increase ( B ) The frequency will stay the same ( C ) The frequency will decrease ( D ) None of these
Last Answer : ( C ) The frequency will decrease
Description : What is the effect on the undamped natural frequency of a single-degree-of-freedom system if the stiffness of one or more of the springs is increased? (A) The frequency will increase (B) The frequency will stay the same (C) The frequency will decrease (D) None of these
Last Answer : (A) The frequency will increase
Description : What is the effect on the undamped natural frequency of a single-degree-of-freedom system if the mass of the system is increased? A) The frequency will increase (B) The frequency will stay the same (C) The frequency will decrease (D) None of these
Last Answer : (C) The frequency will decrease
Description : Why is damping needed in a practical servo system?
Last Answer : . To minimize overshoot and/or oscillations.
Description : Define servo system. Draw the block diagram of DC Servo System.
Last Answer : Definition: Servo system is defined as automatic feedback control system working on error signals giving the output as mechanical position, velocity or acceleration. 1) The servo system consists of error ... , DC motor, DC gear system and the DC load whose position is to be changed.
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 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 : In lag compensator the damping ratio, gain and steady state error (ess) are (a) Decreases, Decreases and Increases (b) Decreases, Increases and Increases (c) Increases, Increases and Decreases (d) Increases, Decreases and Decreases
Last Answer : In lag compensator the damping ratio, gain and steady state error (ess) are Increases, Decreases and Decreases
Description : For a 2nd order feedback control system, the peak resonance magnitude should be Mp ≤ 1.15. Hence the damping ratio (δ) is (a) 0.1 (d) 0.5 (c) 0.707 (d) 1
Last Answer : For a 2nd order feedback control system, the peak resonance magnitude should be Mp ≤ 1.15. Hence the damping ratio (δ) is 0.5
Description : The natural frequency (in Hz) of free longitudinal vibrations is equal to a) Square root (k/m) / (2π) b) Square root (g/δ) / (2π) c) 0.4985/δ d) all of the mentioned
Last Answer : d) all of the mentioned
Description : The natural frequency (in Hz) of free longitudinal vibrations is equal to a) 1/2π√s/m b) 1/2π√g/δ c) 0.4985/δ d) all of the mentioned
Description : The time constant of the servo-mechanism can be decreased by
Last Answer : The time constant of the servo-mechanism can be decreased by decreasing the inertia of the system
Description : What is a servo motor and how does it work?
Last Answer : It is a simple electrical motor that is operated by AC or DC signal in order to provide a precise angular motion for a given electrical signal.
Description : What is the job of a servo in a transmission?
Last Answer : servo motor use in many types mechanism so its verius type of transmission wich type you need to know
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 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 : 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 : 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 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 : 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 : 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 damping factor of a particular system is unity, the system response will be
Last Answer : The damping factor of a particular system is unity, the system response will be critically damped
Description : The effect of error damping is to?
Last Answer : The effect of error damping is to reduce steady state error.
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 : 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 : If ωmax is the frequency at which the peak amplitude occurs and ωn is the natural frequency of the system then In a forced vibration system with damping, the higher the damping, A) More will be ... and ωmax is independent of damping in this system D) The difference between ωn and ωmax will be zero
Last Answer : A) More will be the difference between ωn and ωmax
Description : The effect of damping on the natural frequency of the system is to A) Reduce it considerably B) Increase it considerably C) Reduce it marginally D) Increase it marginally
Last Answer : C) Reduce it marginally
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 : 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 : 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 : 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 : In a properly designed servo system that has an oscillating input (order), what should be the response of the load?
Last Answer : It should oscillate.
Description : Ratio of the rotor reactance X to the rotor resistance R for a two-phase servo motor (A) is equal to that of a normal induction motor (B) is less than that of a normal induction motor (C) ... than that of a normal induction motor (D) may be less or greater than that of a normal induction motor
Last Answer : C
Description : he dipole magnetic moment (μ) is directly proportional to nuclear spin (I), connected by a constant called the A. Gyromagnetic ratio (γ) B. Planck's constant (h) C. Nuclear susceptibility (χ) D. Chemical shift (δ)
Last Answer : Gyromagnetic ratio (γ)
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
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 : The response of an Undamped system under resonance will be a. very large b. infinity c. zero
Last Answer : b. infinity
Description : A bed of spherical particles (specific gravity 2.5) of uniform size 1500 μm is 0.5 m in diameter and 0.5 m high. In packed bed state, the porosity may be taken as 0.4. Ergun's equation for the above fluid-particle ... fluidisation velocity, VOM is (A) 12 mm/s (B) 16 mm/s (C) 24 mm/s (D) 28 mm/s
Last Answer : (B) 16 mm/s
Description : A bed of spherical particles (specific gravity 2.5) of uniform size 1500 μm is 0.5 m in diameter and 0.5 m high. In packed bed state, the porosity may be taken as 0.4. Ergun's equation for the above fluid-particle system ... What is the porosity of the fluidised bed? (A) 0.2 (B) 0.5 (C) 0.7 (D) 0.8
Last Answer : (C) 0.7
Description : The loop transfer of a system is G(s) H(s) = 5/(s+1) (2s+1)(3s+1) which has the phase crossover frequency fc = 0.16 Hz. The gain margin (dB) of the system is (a) 6 (b) 4 (c) 2 (d) 0
Last Answer : The loop transfer of a system is G(s) H(s) = 5/(s+1) (2s+1)(3s+1) which has the phase crossover frequency fc = 0.16 Hz. The gain margin (dB) of the system is 6
Description : For a type three-control system the asymptote at lower frequency will have a slope A) – 6 db per octave B) – 18 db per octave C) – 20 db per octave D) – 60 db per octave
Last Answer : b
Description : Calculate damping ratio if mass = 200Kg, ω = 20rad/s and damping coefficient = 800 N/m/s A. 0.03 B. 0.04 C. 0.05 D. 0.06
Last Answer : A. 0.03
Description : Calculate damping ratio from the following data: mass = 200Kg ω = 20rad/s damping coefficient = 1000 N/m/s a) 0.03 b) 0.04 c) 0.05 d) 0.06
Last Answer : b) 0.04