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 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 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 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 : For an under damped harmonic oscillator, resonance A Occurs when excitation frequency is greater than undamped natural frequency B Occurs when excitation frequency is less than undamped natural frequency C Occurs when excitation frequency is equal to undamped natural frequency D Never occurs
Last Answer : C Occurs when excitation frequency is equal to undamped natural frequency
Description : During resonance A the Vibrations remains unaffected B no vibration occurs C low amplitude of vibration occurs D high amplitude of vibration occurs
Last Answer : D high amplitude of vibration occurs
Description : During resonance A. High amplitude of vibration occurs B. Low amplitude of vibration occurs C. No vibration occurs D. Vibration remains unaffected
Last Answer : A. High amplitude of vibration occurs
Description : For an under damped harmonic oscillator, resonance a) occurs when excitation frequency is greater than undamped natural frequency b) occurs when excitation frequency is less than undamped natural frequency c) occurs when excitation frequency is equal to undamped natural frequency d) never occurs
Last Answer : c) occurs when excitation frequency is equal to undamped natural frequency
Description : For an underdamped harmonic oscillator, resonance ______. (A) occurs when excitation frequency is greater than the undamped natural frequency (B) occurs when excitation frequency is less than the ... ) occurs when excitation frequency is equal to the undamped natural frequency (D) never occurs
Last Answer : (C) occurs when excitation frequency is equal to the undamped natural frequency
Description : Time required to complete one cycle is known as A. Idle time B. Periodic time C. Both D. None
Last Answer : B. Periodic time
Description : The reciprocal of the interval of time by a vibrating body to complete a cycle is called A Period B Frequency C Resonance D None of the mentioned
Last Answer : B Frequency
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 : In steady state forced vibrations, the amplitude of vibrations at resonance is _____________ damping coefficient. A equal to B directly proportional to C inversely proportional to D independent of
Last Answer : C inversely proportional to
Description : A vibrating system having mass 1kg, a spring of stiffness 1000N/m and damping factor of 0.632 and it is put to harmonic excitation of 10N. Find the amplitude at resonance. A 0.079 B 7.9C 0.056 D 0.00791
Last Answer : D 0.00791
Description : At resonance the phase angle is equal to A 0 0B 180 0 C 120 0 D 90 0
Last Answer : D 90 0
Description : Natural frequency of the system is due to A Resonance B Forced Vibration C Damping D Free Vibration
Last Answer : D Free Vibration
Description : Time taken to complete one cycle is known as A Resonance B Frequency C Period D Damping
Last Answer : C Period
Description : If the damper is not provided and the system is in resonance, which of the following is the correct isolation factor? A. 0B. 1/2 C. 1/4 D. Infinity
Last Answer : D. Infinity
Description : In steady state forced vibrations, the amplitude of vibrations at resonance is __________ damping coefficient. A. Equal to B. Directly proportional to C. Inversely proportional toD. Independent of
Last Answer : C. Inversely proportional to
Description : If the damper is not provided and the system is in resonance, which of the following is the correct isolation factor? A. 0 B. 0.5 C. 0.25 D. Infinite
Last Answer : D. Infinite
Description : In the case of steady state forced vibration at a resonance, the amplitude of vibration is A) Inversely proportional to damping coefficient B) Inversely proportional to damping ratio C) Inversely proportional to resonant frequency D) Directly proportional to resonant frequency
Last Answer : B) Inversely proportional to damping ratio
Description : Natural frequency of the system is due to A) Free vibration B) Forced vibration C) Resonance D) Damping
Last Answer : A) Free vibration
Description : Resonance is a phenomenon when the frequency of external exciting force is A) Twice the natural frequency of the system B) Half the natural frequency of the system C) Same as the natural frequency of the system D) None of the above
Last Answer : C) Same as the natural frequency of the system
Description : n steady state forced vibrations, the amplitude of vibrations at resonance is _____________ damping coefficient. a) equal to b) directly proportional to c) inversely proportional to d) independent of
Last Answer : c) inversely proportional to
Description : The response of an Undamped system under resonance will be a. very large b. infinity c. zero
Last Answer : b. infinity
Description : If the damper is not provided and the system is in resonance, which of the following is the correct isolation factor?(A) 0 (B) 0.5 (C) 0.25 (D) Infinite
Last Answer : (D) Infinite
Description : In steady state forced vibrations, the amplitude of vibrations at resonance is _____________ damping coefficient. (A) equal to (B) directly proportional to (C) inversely proportional to (D) independent of
Last Answer : (C) inversely proportional to
Description : If the damper is not provided and the system is in resonance, which of the following is the correct isolation factor? a) 0 b) 1/2 c) 1/4 d) Infinity
Last Answer : d) Infinity
Description : In which of the cases the factor c = 0? a) When there is damping b) No damping c) Resonance d) c is never 0
Last Answer : b) No damping
Description : In steady state forced vibrations, the amplitude of vibrations at resonance is _____________ damping coefficient. a) equal to b) directly proportional toc) inversely proportional to d) independent of
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 : 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 : 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 : 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 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 : 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 : 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 : 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 : 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 : 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 : 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 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 : 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 : 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 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 : 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