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 : 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 : 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 : During vibrations any machine has unbalanced force of 392N and if it transmitted force of magnitude 58.3N then transmissibility value is A 0.481 B 0.822 C 0.148 D 0.296
Last Answer : C 0.148
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 : Dynamic vibration absorber is suitable for A) Constant speed machine B) Varying speed machine C) zero speed machine D) None of the above
Last Answer : A) Constant speed machine
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 : The condition of a machine can be determined using_________ severity charts.
Last Answer : Ans- Vibration
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 : 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 : Which of the following systems produce a vibration in the foundation? (A) Coupled machine (B) Uncoupled machine (C) Balanced machine (D) Unbalanced machine
Description : When a periodic disturbing force is applied to a machine, the force is transmitted to the foundation by the means of spring. a) True b) False
Last Answer : a) True
Description : Which of the following systems produce a vibration in the foundation? a) Unbalanced machine b) Balanced machine c) Coupled machine d) Uncoupled machine
Last Answer : a) Unbalanced machine
Description : In Beizer Curve, the curve follows __________ a.the control points b.the shape of the defining polygon c.the defining points d.none of the above
Last Answer : b.the shape of the defining polygon
Description : In Beizer Curve, the curve follows a.the control points b.the shape of the defining polygon c.the defining points d.none of the above
Description : The curve that follows a convex hull property is: a.Cubic spline b.B-spline c.Bezier curve d.Both (b) and (c)
Last Answer : b.B-spline
Description : When acetone is added in a two layer mixture of methyl isobutyl ketone and water at 30°C, the acetone distributes between the two layers and the composition of the layer follows two solubility curves. For this system ... at the concentration of the plait point (D) All (A), (B) and (C
Last Answer : (D) All (A), (B) and (C
Description : The transitional middle portion of a logistic curve follows (A) A geometric growth (B) A logarithmic growth (C) A first over curve (D) A constant rate
Last Answer : (D) A constant rate
Description : If a linear traverse follows a sharp curve round a large lake where it is difficult to have long legs, the accuracy of the traverse may be improved by (A) Taking short legs (B) Making ... (C) Making a subsidiary traverse to determine the length of a long leg (D) All the above
Last Answer : (C) Making a subsidiary traverse to determine the length of a long leg
Description : Distribution of shear intensity over a rectangular section of a beam, follows: (A) A circular curve (B) A straight line (C) A parabolic curve (D) An elliptical curve
Last Answer : Answer: Option C
Description : The stress-strain curve concrete in compression follows [ A ] a straight line [ B ] a rectangular parabolic curve [ C ] a semi circular arc [ D ] a cubic parabola
Last Answer : [ B ] a rectangular parabolic curve
Description : If the population growth follows a logistic curve, the maximum sustainable yield: (A) is equal to half the carrying capacity. (B) is equal to the carrying capacity. (C) depends on growth rates. (D) depends on the initial population.
Last Answer : (A) is equal to half the carrying capacity.
Description : Often an unbalance of forces is produced in rotary or reciprocating machinery due to the ______ * 1 point (A) Centripetal forces (B) Centrifugal forces (C) Friction forces (D) Inertia forces
Last Answer : (D) Inertia forces
Description : If the spring mass system with m and spring stiffness k is taken to very high altitude, the natural frequency of longitudinal vibrations * 1 point (A) increases (B) decreases (C) remain unchanged (D) may increase or decrease depending upon the value of the mass
Last Answer : (C) remain unchanged
Description : The speed at which the shaft runs so that the additional deflection from the axis of rotation of the shaft becomes infinite, is known as _________ * 1 point (A) Whirling speed (B) Rotational speed (C) Stabilizing speed (D) Reciprocating speed
Last Answer : (A) Whirling speed
Description : Frequency is equal to ______. * 1 point (A) time period (B) 1/time period (C) *time period (D) /time period
Last Answer : (B) 1/time period
Description : What are deterministic vibrations? * (A)Vibrations caused due to known exciting force (B)Vibrations caused due to unknown exciting force (c) Vibrations which are aperiodic in nature (D) None of the above
Last Answer : (A)Vibrations caused due to known exciting force
Description : Equilibrium Method is in accordance with which of the following principle? * 1 point (A) Taylor's principle (B) D'Alembert's principle (C) Energy conservation principle (D) None of the above
Last Answer : (B) D'Alembert's principle
Description : According to which method, maximum kinetic energy at mean position is equal to maximum potential energy at extreme position? * 1 point (A) Energy method (B) Rayleigh's method (C) Equilibrium method (D) All of the above
Last Answer : (B) Rayleigh's method
Description : A mass of 1 kg is attached to two identical springs each with stiffness k = 20 kN/m as shown in the figure. Under frictionless condition, the natural frequency of the system in Hz is close to * 1 point (A) 32 (B) 23 (C) 16 (D) 11
Last Answer : (A) 32
Description : What are discrete parameter systems? *1 point (A) Systems which have infinite number of degree of freedom (B) Systems which have finite number of degree of freedom (C) Systems which have no degree of freedom (D) None of the above
Last Answer : (B) Systems which have finite number of degree of freedom
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 : The equivalent stiffness of spring connected in parallel having stiffnesses k1 and k2 can be written as * 1 point (A)(1/k1) + (1/k2) (B) (1/k1) - (1/k2) (C) k1 + k2 (D) None of the above
Last Answer : (C) k1 + k2
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 : 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 : When the body vibrates under the influence of external force, then the body is said to be under ___________ . * 1 point (A) free vibrations (B) natural vibrations (C) forced vibrations (D) damped vibrations
Last Answer : (C) forced vibrations
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 : The natural frequency of a spring-mass system on earth is ωn. The natural frequency of this system on the moon (g of moon = g of earth /6) is * 1 point (A) ωn (B) 0.408ωn (C) 0.204ωn (D) 0.167ωn
Last Answer : (A) ωn
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 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 : 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 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 : 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 : From the following, which one is also known as low-frequency Transducer? (A) Stroboscope (B) Accelerometer (C) Vibrometer (D) None of the above
Last Answer : (C) Vibrometer
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 : The speed at which the shaft runs so that the additional deflection of the shaft from the axis of rotation becomes ___________, is known as critical or whirling speed. (A) zero (B) minimum (C) maximum (D) infinite
Last Answer : (D) infinite