MCQs on Hydrodynamics Step Bearing
1 - Question
This set of Machine Design Multiple Choice Questions & Answers (MCQs) focuses on “Hydrodynamics Bearings”.
Answer the questions 1-7 with respect to this figure
The bearing characteristic number shown in the graph is directly proportional to the unit bearing pressure.a) True
b) False
View Answer
Answer: b
Explanation: BCN=µN/P.
2 - Question
In the graph shown, which regions points the partial metal to metal contact.
a) BC
b) CD
c) Both BC and CD
d) Can’t be determined
View Answer
Answer: a
Explanatiion: BC is the condition of thin film and hence surfaces are not completely separated.
3 - Question
Hydrodynamic lubrication takes place in region?
a) BC
b) CD
c) Both BC and CD
d) None of the mentioned
View Answer
Answer: b
Explanation: In CD thick film of lubrication has developed.
4 - Question
Coefficient of friction is minimum at
a) It is same at each point
b) B
c) C
d) D
View Answer
Answer: c
Explanation: It is minimum at the transition zone.
5 - Question
Bearing modulus is the bearing characteristic number at
a) B
b) C
c) D
d) None of the listed
View Answer
Answer: b
Explanation: BCN modulus is the the BCN number corresponding to the minimum coefficient of friction.
6 - Question
If viscosity of the lubricant is very low than BCN will lie in the region
a) BC
b) Point C
c) CD
d) Can’t be determined
View Answer
Answer: a
Explanation: Due to low viscosity, lubricant will not separate the two surfaces resulting in partial contact.
7 - Question
The fundamental equation for viscous flow is given by ∆pbhᵌ/6µl where symbols have their usual meanings.
a) 6 is to be replaced by 3
b) 6 is to be replaced by 12
c) 6 is to be replaced by 9
d) 6 is to be replaced by 15
View Answer
Answer: b
Explanation: It is givenby ∆pbhᵌ/12µl.
8 - Question
A single transverse weld is preferred over double transverse fillet weld.
a) True
b) False
View Answer
Answer: b
Explanation: A single transverse weld is not preferred because the edge of the plate which is not welded can warp out of shape.
9 - Question
Transverse fillet weld can be designed using the same equations as of parallel fillet weld.
a) True
b) False
View Answer
Answer: b
Explanation: Vice versa is true as strength of transverse fillet weld is greater than that of parallel fillet weld.