Multiple choice question for engineering
1. Thin pieces of split or sawn wood are called:
Answer: c [Reason:] Shingles are commonly used in hilly areas and for building low cost houses. They are nailed to supporting structure to make roof covering.
2. EPDM Rubber is generally used for:
a) 3-in-12 pitch
b) 4-in-12 slope
c) 2-in-12 slope
d) Flat roofs
Answer: d [Reason:] EPDM Rubber is ethylene propylene diene monomer. It is used to create single-ply rubberized roof for a flat or a very low slope roof. It is UV resistant.
3. How many types of composition shingles are there?
Answer: a [Reason:] The two types of composition shingles are organic and fibreglass. It is used to cover pitched or sloping roofs.
4. Synthetic slate is made from:
b) Fibre cement
c) Plastic fibres
Answer: b [Reason:] The fibres in fibre cement are usually wood or cellulose. These cannot be used in freeze-thaw climates, as the fibres may absorb water.
5. Mission or barrel roof tiles are:
Answer: b [Reason:] The barrel tiles are semi-cylindrical in shape. They are laid in alternating columns of convex and concave tiles. They can be produced from clay, metal, concrete or plastic.
6. ________ coating is applied on a metal roof to improve heat – reflective properties.
Answer: c [Reason:] Paint and Zinc is applied to give a good appearance and to prevent corrosion. Oils are used to enhance appearance by bringing out the colour and lustre. It also excludes moisture from copper roofs.
7. The simplest form of wood shingle is:
Answer: c [Reason:] There can be different shapes of wood shingles and shakes. They can be tapered, straight, split or sawn and any two of the above can be combined, except straight-tapered. Rectangular shingles of 14cm length is the simplest form.
8. Liquid roofing is the process of:
a) Water proofing roofs
b) Painting roofs
c) Using glass for roofing
d) Curving R.C.C. roofs
Answer: a [Reason:] It refers to the application of a special liquid coating to any type of roofs. The coating then cures and forms a rubber like water proof membrane. It is cost effective, safe, easy to apply and highly reliable.
9. The CGI sheets produced today, have the pitch of:
a) 1 inch
b) 3 inches
c) 5 inches
d) 7 inches
Answer: b [Reason:] Pitch is the distance between two crests in a corrugated sheet. In corrugated galvanized Iron (CGI) sheets, pitch can range from 1-5 inches. Commonly produced one these days is 3 inch one.
10. Straw thatch roof may last for 50-60 years.
Answer: b [Reason:] Straw thatch and reed thatch are both used after dipping them in fire resistant solutions. Straw thatch is more likely to catch fire, absorb more moisture than reed thatch. Straw thatch can last for 20-25 years while reed thatch can last for 50-60 years.
11. Which of the below ratio is used for R.C.C. roofing?
Answer: d [Reason:] The R.C.C. is used for flat roofs. The most commonly used ratio is 1:1.5:3.
1. Roof may be broadly classified into:
Answer: b [Reason:] The three types are sloping roofs, flat roofs and shell roofs. They can be used according to the place of construction and requirements.
2. The lowest edge of sloping surface of roof is called:
Answer: d [Reason:] Ridge is the apex line of a sloping roof. Rafters are wooden members extending from ridge to eves. Pitch is the inclination of sloping roof to horizontal.
3. _________ Roof has four sloping sides with zero vertical roof lines.
Answer: c [Reason:] Hip roof is difficult to construct compared to flat and gable roof because these have complicated truss and rafter structure.
4. The figure below represents a __________ roof.
Answer: a [Reason:] It is type of shell roof. The two sides are shaped like wings of a butterfly, hence the name. It is not commonly used because it does not provide drainage facility.
5. Ridge piece in a sloping roof is usually a:
Answer: b [Reason:] Ridge piece runs horizontally at the apex. Rafters are then affixed on to this. It is usually a wooden piece or board.
6. How many types of sloping roofs are available?
Answer: d [Reason:] There are 6 types of sloping roofs available. They are steel sloping roofs, lean-to-roofs, couple roofs, couple close roofs, collar beam roofs and trussed roofs.
7. Timber trusses can be built for long spans.
Answer: b [Reason:] Steel trusses are mostly used for longer spans. These are easy to fabricate, install and maintain. They have higher resistance to fire, corrosion (painting) etc….
8. A finishing coat with ________ ratio is provided in Punjab terrace roofs.
Answer: c [Reason:] The finishing coat primarily consists of cow dung and cement mixed together. They are taken in 4:1 ratio, that is 4 parts cow dung to 1 part cement.
9. Which of the below roof types can be used for a span of 4.5 m?
a) Couple close roof
c) Couple roof
d) Collar beam roof
Answer: a [Reason:] Lean-to-roof is usually employed for a span of 2.5m. Couple roof is provided where a span of 3.5m is required. Collar beam roof can be used up to span of 4-6m.
10. A gable roof slopes in ________ direction.
Answer: c [Reason:] A gable roof slopes in two directions in such a way that the end formed by the intersection of slopes is a sloped triangle. It is commonly used in houses, workshops, etc.
11. How many layers of flat tiles are placed in Madras terrace roofs?
Answer: d [Reason:] In Madras terrace roof, firstly wooden joists are placed over steel joists or walls. Then, a course of well burnt bricks is placed in lime mortar, followed by a layer of brick bat concrete. Then 3 layers of flat tiles in lime mortar (1:2) is provided and the roof is finished with 3 coats of plaster.
12. Which of the below is the type of folded plate roof?
c) Corrugated shell
Answer: a [Reason:] Folded plate roofs may be defined as slabs with folds. These folds reduce bending moment and shear force considerably. Cylindrical, Corrugated shell and Ellipsoidal are types of shell roofs.
1. Natural rubber contains polymers of organic compound:
Answer: d [Reason:] Rubber primarily consists of Isoprene. It may contain certain impurities like organic compounds and water.
2. Rubber is extremely water-proof.
Answer: a [Reason:] Rubber consists of mainly hydrocarbons. It also contains resins, fatty acids and sterols. These provide water proofing quality to rubber.
3. What is added to rubber to make it a thermosetting polymer?
Answer: b [Reason:] The process of vulcanization makes rubber get converted into a heavily cross-linked, insoluble and infusible compound. It is done by adding sulphur and litharge (PbO).
4. Rubber latex is used for:
a) Bonding wood plys
b) Bonding rubber to walls
c) Bonding rubber to wood
d) Bonding tools
Answer: c [Reason:] It is a solution of rubber hydrochloride. It has a sticky texture and has excellent adhesive property.
5. Rubber seed oil can be used in:
Answer: a [Reason:] It can be used as a semi-drying oil in paints. It partially hardens when exposed to air unlike other drying oils in paint.
6. Recycled crumb rubber can be used in:
Answer: d [Reason:] Good compressive strength results were obtained when 25% of sand was replaced by rubber. It is economical and conserves sand usage.
7. What is resilience?
Answer: b [Reason:] When rubber is subjected to a load, it deforms. On removal of load, it returns back to its original shape and size. This property is resilience.
8. Rubber bricks are generally used for:
d) Lining pizza ovens
Answer: c [Reason:] Rubber bricks are manufactured from recycles tyres. They are resistant to water and don’t become slippery when wet. They are extensively used as flooring in toilets, pavements and horse stables.
9. Hardness of rubber is measured on which scale?
a) Rockwell scale
b) Shore scale
c) Mohr’s scale
d) Vicker’s scale
Answer: b [Reason:] Hardness is measured in terms of durometer on a shore scale. Shore A is used for soft to medium-hard rubber. Solid rubber has hardness of 40 duro.
10. Rubber wood is eco-friendly and easily available.
Answer: a [Reason:] Unlike other trees grown solely for timber purpose, rubber tree provides latex also. After 25-30 years, its latex yields become lower and they are felled. They are replanted after that.
11. Synthetic rubber is also called:
a) Gum rubber
d) Gum elastic
Answer: c [Reason:] It is sold under different names. Some of them are neoprene, buna-s, hypalon, silastic, etc. Gum rubber, caoutchouc and gum elastic are names used for natural rubber.
1. Seasoning of timber is the process of:
a) Burning timber
b) Adding preservatives
c) Removing water
d) Adding glaze
Answer: c [Reason:] Tree when felled contains sap and high moisture content. To use it for engineering purpose, it has to be dried. The process of drying timber to remove water is called seasoning.
2. Which of the below changes do not occur after seasoning?
a) Increase durability
b) Decrease stiffness
c) Workable timber
d) Reduction in weight
Answer: b [Reason:] Seasoning increases the stiffness of timber. It takes away sap and moisture content and imparts stiffness to timber.
3. Kiln seasoning gives stronger timber.
Answer: b [Reason:] Natural seasoning is the one that gives stronger timber. Kiln seasoning results in weaker, lighter timber.
4. How much time does natural seasoning takes for timber to be properly seasoned?
a) 1-4 years
b) 6-12 months
c) 5-10 months
d) 5-7 years
Answer: a [Reason:] Natural seasoning is a very slow process, as timber is stacked and blowing natural wind seasons it. It may take anywhere from 1-4 years for obtaining properly seasoned timber.
5. Which of the below is a disadvantage of air seasoning?
a) Power requirement
b) Skilled supervision
c) Elaborate equipment
d) Uniformity of seasoning
Answer: d [Reason:] Air or natural seasoning does not require power, skilled supervision and elaborate equipment. These are all advantage of air seasoning. It might not give uniformly seasoned timber.
6. How many methods of artificial seasoning are there?
Answer: c [Reason:] The 5 types are water seasoning, boiling, chemical seasoning, electrical seasoning and kiln seasoning.
7. Which method leaves the timber brittle after seasoning?
a) Water seasoning
b) Kiln seasoning
c) Electric seasoning
Answer: a [Reason:] Timber pieces are totally immersed in running water for 2-4 weeks. The sap, organic matter is carried away by water in water seasoning. It renders the timber brittle.
8. Which of the below chemicals is not used in chemical seasoning?
a) Sodium chloride
c) Sodium hypochlorite
d) Sodium nitrate
Answer: c [Reason:] Chemicals used are dehydrating agents. Timber is immersed in such salt solutions and allowed to reduce water content. Sodium hypochlorite is a disinfectant.
9. Which is the most rapid and effective method of seasoning?
a) Chemical seasoning
b) Electric seasoning
c) Kiln seasoning
d) Natural seasoning
Answer: b [Reason:] Electric seasoning involves passing high electricity through timber. Since, it is a bad conductor of electricity, it gets heated up. It results in rapid seasoning and it is effective as it provides uniform seasoning.
10. In kiln seasoning, the temperature of air inside chamber and humidity is high.
Answer: b [Reason:] Seasoning starts at low temperature and high humidity. As it proceeds, conditions are gradually altered. At the end, in the chamber, temperature is high and humidity is low.
11. For how long is timber boiled in water in the seasoning method of boiling?
a) 3-4 hours
b) 1-2 hours
c) 5-6 hours
d) 10-12 hours
Answer: a [Reason:] Timber is immersed in water and allowed to boil for 3-4 hours. Then it is taken into shed and dried very slowly.
1. The sieve sets for coarse aggregate ranges from:
Answer: c [Reason:] According to IS 565, the sieve sets are 80mm, 40mm, 20mm, 10mm, 4.75mm for coarse aggregates.
2. The aggregate sample for the sieve analysis is placed on:
a) Largest sieve
b) Smallest sieve
c) 40mm IS sieve
d) 4.75mm IS sieve
Answer: a [Reason:] Only if sample is placed on largest sieve size, it can be sorted, according to each smaller sieve size below.
3. What is a receiver in a sieve analyser?
a) Round pan on top
b) First sieve
c) Last sieve
d) Round pan at base
Answer: d [Reason:] At the base of all the sieve sets, round pan is placed to collect the particles finer than the last sieve size. It is called the receiver.
4. How is percentage retained on each sieve calculated?
Answer: b [Reason:] The percentage retained is calculated by dividing weight of sample retained by the weight of the total sample, taken in beginning of test.
5. In how many ways can sieve analysis be carried out?
Answer: a [Reason:] The 5 methods are throw-action, horizontal, tapping, wet and air circular jet.
6. Under what circumstance is a wet sieve analysis carried out?
a) Sample is washed
b) Moisture content is high in sample
c) Sample contains organic matter
d) Very fine powdered sample
Answer: d [Reason:] Sometimes samples contain very fine powders which tend to agglomerate. In dry sieve analysis, it would lead to clogging of meshes and it makes analysis difficult.
7. Which of the below is a limitation of performing sieve analysis?
a) Time consuming
c) Particle shape
d) Particle size
Answer: c [Reason:] The shape of particles is assumed to be nearly round or spherical, so that they pass through square opening. For elongated, flaky particles it will be difficult.
8. A narrow gradation is also called:
a) Gap gradation
b) Uniform gradation
c) Rich gradation
d) Open gradation
Answer: b [Reason:] A graph is plotted after performing sieve analysis. It shows different curves. A narrow gradation is also called uniform gradation. It shows that the aggregate is of approximately the same size.
9. For how long is the mechanical vibrator shaked?
a) 15-20 minutes
b) 5 minutes
c) 10-15 minutes
d) 30 minutes
Answer: a [Reason:] As per IS code 2720 Part 4. Mechanical vibrator is switched on and allowed to vibrate for 15-20 minutes. It ensures proper grading of particles.
10. For fine aggregates that is, sample passing through 4.75mm IS sieve, how much sample
should be taken?
a) 5 kg
b) 1 kg
c) 2 kg
d) .5 kg
Answer: b [Reason:] IS 2720 gives the specifications. It requires using sample weighing 5 kg for coarse aggregates and 1 kg for fine aggregates.
11. Gradation affects the properties of an aggregate.
Answer: a [Reason:] Gradation affects properties like bulk density, physical stability and permeability. With careful selection of the gradation, desired properties can be achieved.