Description : Free torsional vibrations of a single motor system increases with increase in polar moment of inertia. a) True b) False
Last Answer : b) False
Description : Free torsional vibrations will occur in a two rotor system only if both rotors have same frequency. a) True b) False
Last Answer : a) True
Description : If the mass moment of inertia is increased to four times, then what will be the effect on free torsional vibrations of a single motor system? a) Increases 4 times b) Increases 2 times c) Decreases 4 times d) Decreases 2 times
Last Answer : d) Decreases 2 times
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 : 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 : For the same dimensions of a beam, transverse vibrations have a lower frequency than longitudinal frequency.a) True b) False
Description : A body of mass 20 kg is suspended from a spring which deflects 20mm under this load. Calculate the frequency of free vibrations in Hz. a) 3.5 b) 5 c) 6 d) 7
Last Answer : a) 3.5
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 : f the mass is of 10 Kg, find the natural frequency in Hz of the free longitudinal vibrations. The displacement is 0.01mm. a) 44.14 b) 49.85 c) 43.43 d) 46.34
Last Answer : b) 49.85
Description : If the polar moment of inertia is increased to four times, then what will be the effect on free torsional vibrations of a single motor system? A. Increases 4 times B. Increases 2 times C. Decreases 4 times D. Decreases 2 times
Last Answer : B. Increases 2 times
Description : f the length inertia is decreased to nine times, then what will be the effect on free torsional vibrations of a single motor system? a) Increases 3 times b) Increases 9 times c) Decreases 9 times d) Decreases 3 times
Last Answer : a) Increases 3 times
Description : If the polar moment of inertia is increased to four times, then what will be the effect on free torsional vibrations of a single motor system? a) Increases 4 times b) Increases 2 times c) Decreases 4 times d) Decreases 2 times
Last Answer : b) Increases 2 times
Description : f the spring displacement is high then the frequency of the spring increases. a) True b) False
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 : What is meant by critical damping coefficient? A Frequency of damped free vibrations is less than zero B The motion is aperiodic in nature C Both a. and b. D None of the above
Last Answer : B The motion is aperiodic in nature
Description : In damped free vibrations, which parameters indicate vibrations? A) Natural frequency B) Rate of decay of amplitude C) Both a. and b. D) None of the above
Last Answer : C) Both a. and b.
Description : What is meant by critical damping coefficient? B ( A )Frequency of damped free vibrations is less than zero ( B )The motion is aperiodic in nature ( C )Both a. and b. (D)None of the above
Last Answer : ( B )The motion is aperiodic in nature
Description : What is meant by critical damping coefficient? a. Frequency of damped free vibrations is less than zero b. The motion is aperiodic in nature c. Both a. and b. d. None of the above
Last Answer : b. The motion is aperiodic in nature
Description : In damped free vibrations, which parameters indicate vibrations? a. Natural frequency b. Rate of decay of amplitude c. Both a. and b. d. None of the above
Last Answer : c. Both a. and b.
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 : _______ torsional vibrations will occur in a two-rotor system only if both rotors have the same frequency. (A) Free (B) Forced (C) Unbalanced (D) None of the above
Last Answer : (A) Free
Description : Find the displacement in mm of the free longitudinal vibrations if the Natural frequency is 20 Hz. a) 0.1 b) 0.2 c) 0.5 d) 0.6
Last Answer : d) 0.6
Description : Find the displacement in mm of the free longitudinal vibrations if the Natural frequency is 15 Hz. a) 1.1 b) 1.2 c) 1.5 d) 1.6
Last Answer : a) 1.1
Description : Find the natural frequency in Hz of the free longitudinal vibrations if the displacement is 2mm. a) 11.14 b) 12.38 c) 11.43 d) 11.34
Last Answer : a) 11.14
Description : The natural frequency (in Hz) of free longitudinal vibrations is equal to a) 1/2π√s/m b) 1/2π√g/δ c) 0.4985/δ d) all of the mentioned
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
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
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
Description : In damped vibrations, the amplitude of the resulting vibration gradually diminishes. a) True b) False
Description : Which of the following relation is correct regarding free torsional vibrations of a single motor system? a) Independent of modulus of rigidity b) Independent of polar moment of inertia c) Dependent on mass moment of inertia d) Independent of length of shaft
Last Answer : c) Dependent on mass moment of inertia
Description : f radius of gyration increases then the torsional free vibration increases. a) True b) False
Description : Increasing mass will result in lower frequency. a) True b) False
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 : 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 : Frequency of vibrations is usually expressed in A number of cycles per hour B number of cycles per minute C number of cycles per secondD None of these
Last Answer : C number of cycles per second
Description : In coulomb damping the frequency of damped vibrations is A Equal to that of undamped vibrations B Less than that of undamped vibrationsC More than that of undamped vibrations D Independent of the frequency of undamped vibration
Last Answer : A Equal to that of undamped vibrations
Description : Calculate the static deflection in μm of transverse vibrations if the frequency is 200Hz. A. 6.21 B. 0.621 C. 62.1 D. 0.006
Last Answer : A. 6.21
Description : Which type of frequency measuring instrument has multiple reeds of different natural frequency to measure vibrations? A. Fullarton tachometer B. Frahm Tachometer C. Both A. and B. D. None of the above
Last Answer : B. Frahm Tachometer
Description : In case of viscous damping the frequency of damped vibration is A) Equal to that of undamped vibrations B) Less than that of undamped vibrations C) Greater than that of undamped vibrations D) Independent than that of undamped vibrations
Last Answer : B) Less than that of undamped vibrations
Description : Frequency of vibrations is usually expressed in ( A ) number of cycles per hour ( C ) number of cycles per second C ( B ) number of cycles per minute ( D ) None of these
Last Answer : ( C ) number of cycles per second
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 : Calculate the static deflection in μm of transverse vibrations if the frequency is 200Hz. a) 6 b) 0.6 c) 60 d) 0.006
Last Answer : a) 6
Description : Calculate the natural frequency of transverse vibrations if the static deflection is 0.01mm. a) 157.6 b) 144.8 c) 173.2 d) 154.1
Last Answer : a) 157.6
Description : If the mass of body increases A Frequency increases 4 times B Frequency decreases 4 times C Frequency become half D Frequency become double
Last Answer : C Frequency become half
Description : If the mass of body increases 4 times A Frequency increases 4 times B Frequency decreases 4 times C Frequency become half D Frequency become double
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 : Which of the following is a type of free vibration? A Longitudinal vibrations B Transverse vibrations C Torsional vibrations D A, B and C
Last Answer : D A, B and C
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 of the following is a type of free vibration? A. Longitudinal vibrations B. Transverse vibrations C. Torsional vibrations D. A, B and C
Last Answer : D. A, B and C