Description : A shaft of diameter d carries two discs at its two ends. The lowest torsional frequency is ω n . If the diameter is doubled, then the lowest torsional frequency becomes A 4ω n B ω n /2 C ω n /4 D 4ω n
Last Answer : D 4ω n
Description : A shaft of length l carries two discs at its two ends. The lowest torsional frequency is ω n . If the shaft length is doubled, then the lowest torsional frequency becomes A ω n /2 B ω n /√2 C √2ω n D 2ω n
Last Answer : B ω n /√2
Description : The number of natural frequencies in case of cantilever is A Zero B One C Two D Infinite
Last Answer : D Infinite
Description : The number of natural frequencies in a two rotor system is A. Infinite B. Zero C. Two D. Four
Last Answer : C. Two
Description : In semi-definite system one of the natural frequencies is A Zero B One C Two D Infinite
Last Answer : A Zero
Description : In semidefinite system one of the natural frequencies is A. Zero B. Non-zero C. Infinite one D. One
Last Answer : A. Zero
Description : When the speed of rotation of a shaft equals one of the natural frequencies of the shaft, it is called____________speed.
Last Answer : Ans- Critical
Description : The critical speed of a shaft with a disc supported in between is equal to the natural frequency of the system in A Transverse vibrations B Torsional vibrations C Longitudinal vibrations D None of the mentioned
Last Answer : A Transverse vibrations
Description : The critical speed of a shaft with a disc supported in between is equal to the natural frequency of the system in a) transverse vibrations b) torsional vibrations c) longitudinal vibrations d) none of the mentioned
Last Answer : a) transverse vibrations
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 : 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
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 _________ A. Whirling speed B. Rotational speed C. Stabilizing speed D. Reciprocating speed
Last Answer : A. Whirling speed
Description : In measuring critical speed of shaft experiment, it was found that the frequency ratio is 0.707 when the eccentricity is 0.05 m. what will be the displacement of the system. A. 0.05 m B. 0.005 m C. 0.5 m D. Infinite
Last Answer : A. 0.05 m
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 : In a spring mass system of mass m and stiffness k, the end of the spring are securely fixed and mass is attached to intermediate point of spring. The natural frequency of longitudinal ... is attached decreases D) Decreases as the distance from the bottom end where mass is attached decreases
Last Answer : B) Is minimum when mass is attached to mid point of the spring
Description : A cantilever shaft having 50 mm diameter and length of 300 mm has a disc of mass 100 kg at its free enD. The Young’s modulus for the shaft material is 200 GN/m 2 . Calculate the natural longitudinal frequency in Hz. A. 575B. 625 C. 525 D. 550
Last Answer : A. 575
Description : A cantilever shaft having 50 mm diameter and length of 300 mm has a disc of mass 100 kg at its free end. The Young’s modulus for the shaft material is 200 GN/m 2 . Calculate the natural longitudinal frequency in Hz. a) 575 b) 625 c) 525 d) 550
Last Answer : a) 575
Description : FFT analyzer can be used to find the ___________. (A) natural frequencies (B) mode shapes(C) both natural frequencies and mode shapes (D) none of the above
Last Answer : (C) both natural frequencies and mode shapes
Description : The number of distinct natural frequencies for an n-degree-of-freedom system can be a. 1 b. ∞ c. n
Last Answer : c. n
Description : The number of natural frequency in two rotor system is A Zero B Infinite C Two D One
Last Answer : C Two
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 : 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 : The vibrations can be controlled by A. Controlling the natural frequencies B. Using proper damping devices C. Introducing vibration absorbers and vibration isolators D. All the above
Last Answer : D. All the above
Description : The vibrations perpendicular to the shaft axis are known as A Transverse B Longitudinal C Torsional D None of the mentioned
Last Answer : A Transverse
Description : The factor which affects the critical speed of a shaft is a) diameter of the disc b) span of the shaft c) eccentricity d) all of the mentioned
Last Answer : d) all of the mentioned
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 : Critical speed is expressed as A rotation of shaft in degrees B rotation of shaft in radians C rotation of shaft in minutes D natural frequency of the shaft
Last Answer : D natural frequency of the shaft
Description : For the same dimensions of the shaft which of the following has the greater natural frequency? A. Transverse B. Longitudinal C. Depends on thickness D. Depends upon length
Last Answer : B. Longitudinal
Description : Critical speed of shaft and disc system A) Is equal to natural frequency of the system in transverse vibration B) Is equal to natural frequency of the system in torsional vibration C) Is ... of the system in longitudinal vibration D) Bears no relationship to any of the system natural frequency
Last Answer : A) Is equal to natural frequency of the system in transverse vibration
Description : Critical speed is expressed as a) rotation of shaft in degrees b) rotation of shaft in radians c) rotation of shaft in minutes d) natural frequency of the shaft
Last Answer : d) natural frequency of the shaft
Description : Critical speed is expressed as ______. A) rotation of the shaft in degrees (B) rotation of the shaft in radians (C) rotation of the shaft in minutes (D) the natural frequency of the shaf
Last Answer : (D) the natural frequency of the shaft
Description : For the same dimensions of the shaft which of the following has the greater natural frequency? (A) Transverse (B) Longitudinal (C) Depends on thickness (D) Depends upon length
Last Answer : (B) Longitudinal
Description : For the same dimensions of the shaft which of the following has the greater natural frequency? a) Transverse b) Longitudinal c) Depends on thickness d) Depends upon length
Last Answer : b) Longitudinal
Description : A cantilever shaft having 50 mm diameter and a length of 300mm has a disc of mass 100 kg at its free end. The Young’s modulus for the shaft material is 200 GN/m^2. Determine the static deflection of shaft in mm. A 0.144 B 0.244 C 0.344 D 0.444
Last Answer : A 0.144
Description : A cantilever shaft having 50 mm diameter and a length of 300 mm has a disc of mass 100 kg at its free end. The Young’s modulus for the shaft material is 200 GN/m 3 . Determine the static deflection of the shaft in mm. a) 0.147 b) 0.213 c) 0.132 d) 0.112
Last Answer : a) 0.147
Description : A cantilever shaft having 50 mm diameter and a length of 300 mm has a disc of mass 100 kg at its free end. The Young’s modulus for the shaft material is 200 GN/m 2 . Determine the frequency of transverse vibrations of the shaft. a) 31 b) 35 c) 37 d) 41
Last Answer : d) 41
Description : A cantilever shaft has a diameter of 6 cm and the length is 40cm, it has a disc of mass 125 kg at its free end. The Young’s modulus for the shaft material is 250 GN/m2. Calculate the static deflection in nm. a) 0.001 b) 0.083c) 1.022 d) 0.065
Last Answer : a) 0.001
Description : If the mass of the constraint is negligible then what is the kinetic energy of the system? a) 0 b) Half the value c) Double the value d) Infinite
Last Answer : a) 0
Description : The natural frequency of a system is a function of A The stiffness of the system B The mass of the system C Both A and B D None of the mentioned
Last Answer : C Both A and B
Description : For a two-rotor system, the length of one shaft (A) is twice the other (B), then what is the relation between the mass moment of inertia of the shafts. A 2I(A) = I(B) B I(A) = 2I(B) C I(A) = I(B) D 2I(A) = 3I(B)
Last Answer : A 2I(A) = I(B)
Description : When the particles of the shaft or disc move in a circle about the axis of the shaft, then the vibrations are known as ___________ . A Longitudinal vibrations B Transverse vibrations C Torsional vibrations D None of these
Last Answer : C Torsional vibrations
Description : When the particles of the shaft or disc move in a circle about the axis of the shaft, then the vibrations are known as ___________ . A. longitudinal vibrations B. transverse vibrations C. torsional vibrations D. none of these
Last Answer : C. torsional vibrations
Description : If the particle of a body vibrate along a circular arc, whose centre lies on the axis of the shaft then the body is said to have A) Transverse vibration B) Longitudinal vibration C) Torsional vibration D) None of the above
Last Answer : C) Torsional vibration
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 are discrete parameter systems? 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 are discrete parameter systems?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 : The frame consists of a steel beam welded rigidly to two vertical channels. An eccentric exciter weighing 250 N is attached to the beam, which weighs 10 KN and is used to excite the frame. The unbalance weight of ... ends, magnification factor at resonance is A. 307.5 B. 3.075 C. 30.75 D. 0.3075
Last Answer : C. 30.75