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 : A 100 kg flywheel having a radius of gyration of 1 m is rotating at 1000 rpm. The angular momentum of the flywheel about its axis of rotation, in kg m2/s is a.1000 b.107 dynes c.10000 d.10470 e.5235
Last Answer : d. 10470
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 : The condition to be fulfilled in the design of spring for vibration isolation of a system where excitation is due to a rotating unbalance is A) ω ωn D) ω >> ωn
Last Answer : A) ω
Description : In case of an eccentric loading on a bracket subjected to moment M, the tangential force developed in any rivet, at right angles to its radius vector r is (A) Mr/ r² (B) r²/Mr (C) Mr²/ r² (D) Mr/ r²
Last Answer : (A) Mr/ r²
Description : Which formula is used to calculate mass moment of inertia (I G ) of a circular rim about the axis through centre of gravity? a. mr 2 /2b. mr 2 /12 c. mr 2 /4 d. mr 2
Last Answer : d. mr 2
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
Description : Calculate damping ratio from the following data: mass = 200Kg ω = 20rad/s 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 critical damping coefficient in N/m/s from the following data: mass = 100Kg ω = 40rad/s a) 25,132 b) 26,132 c) 27,132 d) 28,132
Last Answer : a) 25,132
Description : Calculate critical damping coefficient in Ns/m from the following data. mass = 200Kg ω = 20rad/sa) 25,132 b) 26,132 c) 27,132 d) Not possible
Last Answer : d) Not possible
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 : A larger force on a rotating body results in larger _______. (1) Mass (2) Torque (3) Axis of rotation (4) Centre of mass
Last Answer : (3) Axis of rotation
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 : 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 : When a mass is rotating in a plane about a fixed point, its angular momentum is directed along: (1) the tangent to the orbit (2) a line perpendicular to the plane of rotation (3) the line making an angle of 45° to the plane of rotation (4) the radius
Last Answer : (2) a line perpendicular to the plane of rotation
Description : When heavy rotating masses are connected by a shaft and equal and opposite torques are applied to these masses (rotors) A. The rotors vibrate torsionally in the same direction. B. The rotors vibrate torsionally ... on the axis of shaft which remains undisturbed by vibration. D. Both (B) and (C)
Last Answer : D. Both (B) and (C)
Description : A centrifugal filtration unit operating at a rotational speed of w has inner surface of the liquid (density ρL) located at a radial distance R from the axis of rotation. The thickness of the liquid film is δ and no cake is formed. The ... . ρL (C) ½w 2 . δρL (2R + δ) (D) ½w 2 . R . ρL(R + 2δ)
Last Answer : (C) ½w 2 . δρL (2R + δ)
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 : For a fluid rotating at constant angular velocity about vertical axis as a rigid body, the pressure intensity varies as the (A) Square of the radial distance (B) Radial distance linearly (C) Inverse of the radial distance (D) Elevation along vertical direction
Last Answer : (A) Square of the radial distance
Description : The maximum acceleration of a particle moving with simple harmonic motion is ____. A. ω B. ω.r C. ω / 2 π D. 2 π / ω
Last Answer : B. ω.r
Description : The maximum acceleration of a particle moving with simple harmonic motion is ____. (A) ω (B) ω.r (C) ω / 2 π (D) 2 π / ω
Last Answer : (B) ω.r
Description : In vibration isolation system, if ω/ωn, then the phase difference between the transmitted force and the disturbing force is A 0° B 90° C 180° D 270°
Last Answer : C 180°
Description : In vibration isolation system, if ω/ω n > 1, then the phase difference between the transmitted force and the disturbing force is A. 0° B. 90° C. 180° D. 270°
Last Answer : C. 180°
Description : In vibration isolation system, if ω/ω n , then the phase difference between the transmitted force and the disturbing force is a) 0° b) 90° c) 180° d) 270°
Last Answer : c) 180°
Description : In vibration isolation system, if ω/ω n , then the phase difference between the transmitted force and the disturbing force is a) 0° b) 90° c) 180° d) 270
Description : In vibration isolation system, if ω/ω n > 1, then the phase difference between the transmitted force and the disturbing force is a) 0° b) 90° c) 180° d) 270°
Description : The two resonant frequency ratio (ω/ ω2) in a dynamic vibration absorber system for a mass ratio 0.2 are given by A) 0 ; 1.0 B) 0.801 ; 1.248 C) 0.458 ; 1.124 D) 0.642 ; 1.558
Last Answer : B) 0.801 ; 1.248
Description : The natural frequency of a spring-mass system on earth is ω n . The natural frequency of this system on the moon (g moon = g earth /6) is a) ω n b) 0.408ω n c) 0.204ω n d) 0.167ω n
Last Answer : a) ω n
Description : According to D' Alembert's principle, m (d 2 x/ dt 2 ) + c (dx/dt) + Kx =0 is the differential equation for damped free vibrations having single degree of freedom. What will be the solution to this differential equation if the system is ... Φ) C x = (A - Bt) e - ωt D x = X e - ξωt (cos ω d t + Φ)
Last Answer : A x = (A + Bt) e – ωt
Description : According to D' Alembert's principle, m (d 2 x/ dt 2 ) + c (dx/dt) + Kx =0 is the differential equation for damped free vibrations having single degree of freedom. What will be the solution to this differential equation if the system is ... ) C. x = (A - Bt) e - ωt D. x = X e - ξωt (cos ω d t + Φ
Last Answer : A. x = (A + Bt) e – ωt
Description : Which among the following is the fundamental equation of S.H.M.? A. x + (k / m) x =0 B. x + ω 2 x =0 C. x + (k/ m) 2 x =0 D. x 2 + ωx 2 =0
Last Answer : B. x + ω 2 x =0
Description : Which among the following is the fundamental equation of S.H.M.? A) x + (k / m) x =0 B) x + ω 2 x =0 C) x + (k/ m) 2 x =0 D) x 2 + ωx 2 =0
Last Answer : B) x + ω 2 x =0
Description : According to D' Alembert's principle, m (d 2 x/ dt 2 ) + c (dx/dt) + Kx =0 is the A differential equation for damped free vibrations having single degree of freedom. What will be the solution to this differential equation if the system is ... (C)x = (A - Bt) e - ωt ( D )x = X e - ξωt (cos ω d t + Φ
Last Answer : ( A ) x = (A + Bt) e – ωt
Description : According to D' Alembert's principle, m (d 2 x/ dt 2 ) + c (dx/dt) + Kx =0 is the differential equati damped free vibrations having single degree of freedom. What will be the solution to this differ equation if the system is critically ... c. x = (A - Bt) e - ωt d. x = X e - ξωt (cos ω d t + Φ)
Last Answer : a. x = (A + Bt) e – ωt
Description : Which among the following is the fundamental equation of S.H.M.? a. x+(k/m)x=0 b. x+ω 2 x=0 c. x+(k/m) 2 x=0 d. x 2 + ωx 2 =0
Last Answer : d. x 2 + ωx 2 =0
Description : If Ic = 125 Kg-m 2 and ω= 20 rad/s, calculate the kinetic of the constraint. a) 8333 J b) 7333 J c) 6333 J d) 9333 J
Last Answer : a) 8333 J
Description : δ = (W a 2 b 2 ) / (3 EIL) is the value of deflection for ______ A. simply supported beam which has central point load B. simply supported beam which has eccentric point load C. simply supported beam which has U.D.L. point load per unit length D. fixed beam which has central point load
Last Answer : B. simply supported beam which has eccentric point load
Description : δ = (W a 2 b 2 ) / (3 EIl) is the value of deflection for ______ a. simply supported beam which has central point load b. simply supported beam which has eccentric point load c. simply supported beam which has U.D.L. point load per unit length d. fixed beam which has central point load
Last Answer : b. simply supported beam which has eccentric point load
Description : Centrifugal absorber is used to reduce A) Centrifugal force in rotating system B) Torsional vibration of rotating system C) Vibration in linear system D) Transverse vibrations
Last Answer : B) Torsional vibration of rotating system
Description : A man is standing near the edge of a uniformly rotating platform about an axis passing through its centre. The speed of rotation of the platform will decrease if he a.extends his arms outwards b.moves ... heavy bag from one of his friends standing near by and holds it in his hand e.107 dynes
Last Answer : d. accepts a heavy bag from one of his friends standing near by and holds it in his hand
Description : A man is standing ner the edge of a uniformly rotating platform about an axis passing through its centre. The speed of rotation of the platorm will decrease if he a.extends his arms outwards b.107 ... towards the axis of rotation d.jumps out from that platform e.take out his coat and throws away
Last Answer : a. extends his arms outwards
Description : The moment of inertia of a body does not depend upon a.The angular velocity of the body b.Mass of the body c.The distribution of mass in the body d.The axis of rotation of the body e.None of the above
Last Answer : a. The angular velocity of the body
Description : The moment of inertia of a body does not depend upon its – (1) axis of rotation (2) angular velocity (3) form of mass (4) distribution of mass
Last Answer : (2) angular velocity Explanation: Moment of inertia is the mass property of a rigid body that determines the torque needed for a desired angular acceleration about an axis of rotation. Moment of inertia ... of moments of inertia of the masses making up the whole object, under the same conditions.
Description : The moment of inertia of a body does not depend upon its (1) axis of rotation (2) angular velocity (3) form of mass (4) distribution of mass
Last Answer : angular velocity
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 : 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