This set of Machine Design Multiple Choice Questions & Answers (MCQs) focuses on “Sliding Contact Bearings”.
1. Thick film lubrication describes a phenomenon where two surfaces are _______ separated.
d) None of the mentioned
Explanation: There is no contact between the two surfaces.
2. Hydrodynamic bearing is a self-acting bearing.
Explanation: The pressure in the bearing is created within the system due to rotation of the shaft.
3. A journal bearing is a ______ contact bearing working on the hydrodynamic lubrication and which supports load in____ direction.
a) Sliding, Axial
b) Rolling, Radial
c) Sliding, Radial
d) Rolling, Axial
Explanation: This is how journal bearing works. It derives its name from the portion of the shaft inside the bearing.
4. Partial bearing is preferred over journal bearing.
c) More friction losses
d) Can’t be determined
Explanation: Friction losses are lesser and construction is simple.
5. Temperature rise in partial bearing is ____ than full bearing.
Explanation: Due to lesser friction, temperature rise is less.
6. A clearance bearing is design accurately to keep the radius of journal and bearing equal.
a) Journal radius is kept larger
b) Journal radius is kept smaller
d) Can’t be determined
Explanation: Journal radius is kept smaller.
7. Fitted bearing must be partial bearing.
c) No lubricating space is required
d) Can’t be stated
Explanation: To provide space for lubricating oil.
8. Footstep bearing is an axial load bearing.
b) Thrust load
c) Shear load
d) None of the listed
Explanation: It is a thrust bearing in which shaft end is in contact with bearing surface.
9. Hydrostatic and hydrodynamic lubrication are the same thing.
Explanation: In hydrodynamic, motion is provided by the shaft while in hydrostatic the motion is provided by an external source.
10. If we exclude the cost factor, which bearing is preferred?
c) Both are equally preferred
d) Cannot be determined
Explanation: High load capacity, no starting friction and no rubbing action.
11. If fluid film pressure is high and surface rigidity is low than mode of lubrication is called as elastohydrodynamic lubrication.
Explanation: In such cases, elastic deflections of the parts causes development of the film.
Sanfoundry Global Education & Learning Series – Machine Design.
To practice all areas of Machine Design, here is complete set of 1000+ Multiple Choice Questions and Answers.