half

same

double

unpredictable

the oil film pressure is generated only by the rotation of the journal

the oil film is maintained by supplying oil under pressure

do not require external supply of lubricant

grease is used for lubrication

sleeve bearings

hydrodynamic bearings

thin lubricated bearings

none of the above

ZN/p

p/ZN

Z/pN

N/Zp

0.01 micron

0.1 micron

1 micron

10 microns