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 : The factor which affects critical speed shaft is....... A. eccentricity B. span of shaft C. diameter of disc D. all of above
Last Answer : D. all of above
Description : The factors which affects the critical speed of the shaft is A. Eccentricity B. Diameter of the Disc C. Span of the shaft D. All the above
Last Answer : D. All the above
Description : The critical speed of a shaft is affected by A. Diameter of the disc B. Eccentricity C. Span of shaft D. All of above
Last Answer : D. All of above
Description : The critical speed of a shaft depends upon its A. Mass B. Stiffness C. Mass and stiffnessD. Stiffness and eccentricity
Last Answer : C. Mass and stiffness
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 : 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 : If the static deflection is 1.665×10 -3 m, calculate the critical speed of the shaft in rps. Centre of disc at 0.25m away from centre of axis of shaft. A. 8.64 B. 9.64 C. 10.64 D. 12.2
Last Answer : D. 12.2
Description : Critical speed of shaft having a rotating disc in the middle is A) x/e = 1 / ( r^2 - 1 ) B) x/e = 1 / ( r^2 + 1 ) C) x/e = 1 / ( r^2 - 1^2 ) D) x/e = ( 1 + r) / ( r^2 – 1 )
Last Answer : A) x/e = 1 / ( r^2 - 1 )
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 : 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 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 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 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 : 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 : 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
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 : 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 : Rotor shaft of a large electric motor supported between short bearings at both ends shows a deflection of 1.8 mm in middle of motor. Assuming rotor to be perfectly balanced and supported at knife edges at both ends, likely critical speed (rpm) of shaft isA 350 B 4430 C 705 D 2810
Last Answer : C 705
Description : In most practical situation the speed of rotation of the shaft is usually A) Much below the critical speed B) Much above the critical speed C) Near about the critical speed D) Having no relationship with critical speed
Last Answer : B) Much above the critical speed
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 : 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 : 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 : The ratio of actual damping coefficient to the critical damping coefficient is known as A Magnification Factor B Damping Factor C Logarithmic decrementD None of the mentioned
Last Answer : B Damping Factor
Description : Rotating shafts tends to vibrate violently in transverse directions at certain speed. This speed is called A Critical speedB Whipping speed C Whirling speed D All of the mentioned
Last Answer : D All of the mentioned
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 : If two discs are attached to one shaft at its both end, then it has_____ number of natural frequencies. A Infinite B One C Two D None of the mentioned
Last Answer : B One
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 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 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 : 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 ratio of the actual damping coefficient (c) to the critical damping coefficient (cc ) is known as _________ A Damping factor B Damping coefficient C Resistive factor D Resistive coefficient
Last Answer : A Damping factor
Description : Ratio of actual damping coefficient to critical damping coefficient is called A. Damping Factor B. Angular Factor C. Critical Factor D. None of above
Last Answer : A. Damping Factor
Description : The ratio of the actual damping coefficient (c) to the critical damping coefficient (cc ) is known as _________ ( A ) Damping factor ( B ) Damping coefficient ( C ) Resistive factor ( D ) Resistive coefficient
Last Answer : ( A ) Damping factor
Description : The damping factor is the measure of the relative amount of damping in the existing system with that necessary for the ______ system. (A) underdamped (B) overdamped (C) critical damped (D) all of the above
Last Answer : (C) critical damped
Description : The ratio of the actual damping coefficient (c) to the critical damping coefficient (cc ) is known as _________ a) Damping factor b) Damping coefficient c) Resistive factor d) Resistive coefficient
Last Answer : a) Damping factor
Description : The first critical speed of an automobile running on a sinusoidal road is calculated by (modeling it as a single degree of freedom system) A Resonance B Approximation C Superposition D Rayleigh quotient
Last Answer : A Resonance
Description : The speed at which resonance occurs is called A. Normal Speed B. Idle Speed C. Critical Speed D. None
Last Answer : C. Critical Speed
Description : The first critical speed of an automobile running on a sinusoidal road is calculated by (modeling it as a single degree of freedom system) a) Resonance b) Approximation c) Superposition d) Rayleigh quotient
Last Answer : a) Resonance
Description : The ratio of the maximum displacement of the forced vibration to the deflection due to the static force is known as A Logarithmic decrement B Magnification factor C Damping factor D None of the mentioned
Last Answer : B Magnification factor
Description : Dynamic vibration absorber is suitable for A varying speed machines B constant speed machines C Zero speed range machines D None of the mentioned
Last Answer : B constant speed machines
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 : 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 : Which of the following statements is/are true? A. Torsional vibrations do not occur in a three rotor system, if rotors rotate in same direction B. Shaft vibrates with maximum frequency when rotors ... C. Zero node behavior is observed in rotors rotating in opposite direction D. All of the above
Last Answer : A. Torsional vibrations do not occur in a three rotor system, if rotors rotate in same direction