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

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
by

1 Answer

Answer :

B) critical speed
by

Related questions

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 rotate in same direction C. Zero node behavior is observed in rotors rotating in opposite direction D. All of the above

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

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 rotate in same direction C) Zero node behavior is observed in rotors rotating in opposite direction D) All of the above

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

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 rotate in same direction c. Zero node behavior is observed in rotors rotating in opposite direction d. All of the above

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

The advantage of critical damping is A. That vibrating body come to rest in smallest possible time B. There is no vibration C. That amplitude of vibration is maximum D. The amplitude of vibration is minimum

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Last Answer : A. That vibrating body come to rest in smallest possible time

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 )

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 )

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 equal to natural frequency of the system in longitudinal vibration D) Bears no relationship to any of the system natural frequency

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Last Answer : A) Is equal to natural frequency of the system in transverse vibration

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

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Last Answer : C 705

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 in the opposite direction. C. There is one point on the axis of shaft which remains undisturbed by vibration. D. Both (B) and (C)

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)

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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

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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

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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

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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

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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

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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

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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

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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

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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)

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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

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