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

Correct Answer: all of the mentioned

To determine the critical speed of a shaft which may be subjected to point loads, uniformly distributed load or combination of both, we find the frequency of transverse vibration which is equal to critical speed of a shaft in r.p.s. The Dunkerley’s method may be used for calculating the frequency.
Bissoy MCQ
#Machine Dynamics #Vibratory Motion

Related Questions

Two shafts A and B are made of the same material. The diameter of shaft A is twice as that of shaft B. The power transmitted by the shaft A will be __________ of shaft B.
A Twice
B Four times
C Eight times
D Sixteen times
In ______ machines, the size of the shaft is decided by the critical speed which depends on the deflection of the shaft.
A small
B medium
C large
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A $$2\pi \sqrt {\frac{{\text{q}}}{I}} $$
B $$2\pi \sqrt {{\text{q}}I} $$
C $$\frac{1}{{2\pi }}\sqrt {\frac{{\text{q}}}{I}} $$
D $$\frac{1}{{2\pi }}$$
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A $${\text{r}}\sin \varphi $$
B $${\text{r}}\cos \varphi $$
C $${\text{r}}\tan \varphi $$
D $$\frac{{\text{r}}}{2}\cos \varphi $$
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A Bending moment
B Twisting moment
C Torsional rigidity
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(i) What is global warming? How global warming affects the rapid change of climate? (ii) What are the bad impacts of climate change? (iii) How climate change affects the environment of Bangladesh (iv) How global warming can be minimized (v) What should be the role of students to protect the environment.
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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
The critical speed of a shaft depends upon its
A Mass
B Stiffness
C Mass and stiffness
D Stiffness and eccentricity
The critical speed of a shaft in revolution per second is __________ as that of natural frequency of transverse vibration.
A Same
B Different
C Unpredictable
D None of these

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