DME-II QUIZ-1

In a full journal bearing, the angle of contact of the bearing with the journal is

• 120°

• 270°

• 360°

• 180°

If Z = Absolute viscosity of the lubricant in kg/m-s, N = Speed of the journal in r.p.m., and p = Bearing pressure in N/mm^2, then the bearing characteristic number is

• p N/ Z

• Z N /p

• Z P/N

• P/Z N

A bearing is designated by the number 405. It means that a bearing is of

• light series with bore of 5 mm

• medium series with bore of 15 mm

• heavy series with bore of 25 mm

• light series with width of 20 mm

The rolling contact bearings are known as

• thin lubricated bearings

• thick lubricated bearings

• antifriction bearings

• plastic bearings

The length of the cylinder is usually taken as

• equal to the length of piston

• equal to the length of stroke

• equal to the cylinder bore

• 1.5 times the length of stroke

The side thrust on the cylinder liner is usually taken as ........... of the maximum gas load on the piston.

• 1/5

• 1/10

• 1/8

• 1/4

The crankshaft in an internal combustion engine

• is used to retain the working fluid and to guide the piston

• is a disc which reciprocates in a cylinder

• converts reciprocating motion of the piston into rotary motion and vice versa

• none of the above

To ensure self locking in a screw jack, it is essential that the helix angle is

• equal to friction angle

• larger than friction angle

• smaller than friction angle

• such as to give maximum efficiency in lifting

A screw is said to be over hauling screw, if its efficiency is

• less than 50%

• equal to 50%

• none of these

• more than 50%

-----------is used to connect two non- intersecting, non-coplanar shafts.

• Spur gears

• Bevel gears

• Spiral gears

• None of the above