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 : Which among the following is the fundamental equation of S.H.M.? a. x + (k / m) x =0 b. x + ω2x =0 c. x + (k/ m)2 x =0 d. x2 + ωx2 =0
Last Answer : b. x + ω2x =0
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 : 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 : Consider the steady-state absolute amplitude equation shown below, if ω / ω n = √2 then amplitude ratio (X/Y) =? (X/Y) = √{1 + [ 2ξ (ω/ω n )] 2 } / √{[1 – (ω/ω n ) 2 ] 2 + {2ξ (ω/ω n ) 2 } A. 0 B. 1 C. less than 1 D. greater than 1
Last Answer : B. 1
Description : The equivalent viscous damping coefficient Ceq for coulomb damping is given by A) 4F/πωx B) 4πF/ωx C) πωx/4F D) ωx/4Πf
Last Answer : A) 4F/πωx
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 : The equation of motion for a vibrating system with viscous damping is d 2 x/dt 2 + c/m X dx/dt + k/m X x = 0 If the roots of this equation are real, then the system will be a) over damped b) under damped c) critically damped d) none of the mentioned Ans:a
Last Answer : a) over damped
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 : 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 : 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 : The unbalanced force caused by an eccentric mass m rotating at an angular speed v and located at a distance r from the axis of rotation is 2 a. mr ω 2 b. mgω 2 c. mr ω 2
Last Answer : c. mr ω 2
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 equation of motion for a vibrating system with viscous damping is d 2 x/dt 2 + c/m X dx/dt + s/m X x = 0 If the roots of this equation are real, then the system will be A. over damped B. under damped C. critically damped D. none of the mentioned
Last Answer : A. over damped
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 : The equation m(d 2 x/ dt 2 ) + c (dx/dt) + Kx = F 0 sin ωt is a second order differential equation. The solution of this linear equation is given as A. complementary function B. particular function C. sum of complementary and particular function D. difference of complementary and particular function
Last Answer : C. sum of complementary and particular function
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/ωn < 2, then for all values of damping factor, the transmissibility will be A less than unity B equal to unity C greater than unity D zero
Last Answer : C greater than unity
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 : 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, the transmissibility will be equal to unity, for all values of damping factor, if ω/ωn is A. Equal to 1 B. Equal to √2 C. Less than √2 D. Greater than √2
Last Answer : B. Equal to √2
Description : In the graph shown below, the region in which frequency ratio (ω/ω n ) > √2 is known as____ A. Amplification region B. Isolation region C. Spring controlled region D. None of the above
Last Answer : B. Isolation region
Description : Which of the following vibro-meters have frequency ratio (ω/ω n )
Last Answer : A. Accelerometers
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 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 : The response of a damped forced vibration system A) Leads the system excitation ( for all values of ω/ ωn) B) Lags the system excitation ( for all values of ω/ ωn) C) Leads the system excitation ( for all values of ω/ ωn
Last Answer : B) Lags the system excitation ( for all values of ω/ ωn)
Description : In vibration isolation system, if ω/ω n < 2, then for all values of damping factor, the transmissibility will be a) less than unity b) equal to unity c) greater than unity d) zero
Last Answer : c) greater than unity
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 : 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/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 : n vibration isolation system, if ω/ω n is less than √2 , then for all values of the damping factor, the transmissibility will be a) less than unity b) equal to unity c) greater than unity d) zero
Description : The system governed by the equation stable if 14 a. k is positive b. c and k are positive is dynamically c. c is positive
Last Answer : b. c and k are positive
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 : 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 : 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 : In a dynamic vibration absorber system, under tuned conditions which of the following relation holds good? A K 1 K 2 =M 1 M 2 B K 1 M 2 =M 1 K 2 C K 1 M 1 = K 2 M 2 D none of the mentioned
Last Answer : B K 1 M 2 =M 1 K 2
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 : If the spring mass system with m and spring stiffness k is taken to very high altitude , the natural frequency of longitudinal vibrations A) Increases B) Decreases C) Remain unchanged D) May be increase or decrease depending upon the value of the mass
Last Answer : C) Remain unchanged
Description : Damping factor, ε = A. C/Cc B. C.Cc C. K/m D. K.m
Last Answer : A. C/Cc
Description : Calculate coefficient of viscous damper, if the system is critically damped. Consider the following data: 1. Mass of spring mass damper system = 350 kg 2. Static deflection = 2 x 10 -3 m 3. Natural frequency of the system = 60 rad/sec ... /m B. 80 x 10 3 N-s/m C. 42 x 10 3 N-s/m D. None of the above
Last Answer : C. 42 x 10 3 N-s/m