WorksheetsDAY 20 CIVILEZY CIVILWAR KWA Paints, Plastering, Bearings
Total questions: 10
Worksheet time: 5mins
Which of the following is a desirable property of a good paint under tropical humid climate?
High porosity
Low elasticity
Alkali resistance
Brittle hard film
In stucco plastering, which of the following materials is added to improve plasticity and workability?
Ground marble or limestone dust
Silica sand
Fly ash
Quicklime
Which of the following bearings can support both axial and radial loads?
Journal bearing
Footstep bearing
Thrust bearing
Taper roller bearing
Which of the following defects in painting is primarily caused by moisture or oily surfaces under the paint film?
Blooming
Blistering
Flaking
Fading
Which statement correctly describes the role of driers in oil paints?
They slow down the oxidation process
They accelerate polymerisation and drying
They act as thinners
They provide gloss and hardness
When performing gauged plastering, the proportion of gypsum to lime is generally—
1 : 1 to 1 : 2
1 : 3 to 1 : 4
1 : 5
1 : 6
The material used for bush bearings in heavy machinery is generally —
Cast iron
Gunmetal
Brass
Lead
Which statement about lubrication in bearings is incorrect?
Boundary lubrication occurs when oil film is very thin
Dry lubrication uses graphite or molybdenum disulphide
Full film lubrication prevents metal-to-metal contact
Mixed lubrication occurs only in roller bearings
The main cause of blistering in plastered surfaces is —
Excessive thickness of coats
Improper curing
Poor sand quality
Use of hydraulic lime
In a hydrodynamic bearing, the load is supported due to —
Metallic contact between surfaces
Pressure generated in a lubricant film
Elastic deformation of bearing shell
Spring loading
