# 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

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

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

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

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

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

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

Explanation: It is givenby ∆pbhᵌ/12µl.

8 - Question

A single transverse weld is preferred over double transverse fillet weld.

a) True
b) False

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