Multiple choice question for engineering
1. Why is natural cement used very limitedly?
a) Brown in Colour
b) Standard consistency is not met with
c) Sets too quickly
d) Particle size is too fine
Answer: c [Reason:] Natural cement sets very quickly after addition of water and hence it is not quite workable. Artificial cement is preferred over this.
2. Who invented Portland cement and in which year?
a) William Aspdin, 1824
b) William Aspdin, 1840s
c) Joseph Aspdin, 1840s
d) Joseph Aspdin, 1824
Answer: b [Reason:] Joseph Aspdin patented Portland cement in 1824. William Aspdin, his son is regarded as inventor of modern Portland cement due to his developments in 1840s.
3. What is the average particle size of cement?
a) 15 microns
b) 45 microns
c) 75 microns
d) 100 microns
Answer: a [Reason:] Approximately 95% of cement particles are smaller than 45 microns and the average particle size is 15 microns.
4. What is the meaning of soundness of cement?
a) Ability to flow when mixed
b) Ability to make ringing noise when struck
c) Ability to form strong and sound structure
d) Ability to retain volume after setting.
Answer: d [Reason:] When cement paste hardens and sets, it should not undergo any volume change. Soundness ensures this and is tested using Autoclave expansion test.
5. Time elapsed from the instance of adding water until paste ceases to behave as fluid is called:
a) Initial setting time
b) Final setting time
c) Intermediate setting time
d) Absolute setting time
Answer: a [Reason:] Final setting time is the time required for cement paste to reach certain state of hardness. Option c and d does not exist.
6. Which of the below mentioned is not a result of field test performed on cement?
a) There should not be any lumps
b) It should feel cold when you put your hand in bag of cement
c) The colour should be blackish grey
d) It should not be gritty when rubbed with finger
Answer: c [Reason:] The colour of cement is normally grey with a greenish tint. There are different shades – lighter and darker, but it does not go as dark as blackish grey.
7. Which equipment is used to test setting time of cement?
a) Core cutter
c) Universal testing machine (UTM)
d) Vicat apparatus
Answer: d [Reason:] Core cutter is used to determine dry density of soil. Vibrator is used in sieve analysis. UTM can be used to test various parameters – tension, bending, shear of various materials. Vicat apparatus consists of a needle, used to penetrate the cement paste sample.
8. What is the initial setting time of cement?
a) 1 hour
b) 30 minutes
c) 15 minutes
d) 30 hours
Answer: b [Reason:] As per IS code 4031-part 5, the initial setting time of cement is minimum of 30 minutes. After this cement will start losing its plasticity and will not be workable.
9. Use of coarser cement particles leads to:
a) Low durability
b) Higher strength
c) Low consistency
d) Higher soundness
Answer: a [Reason:] For coarser particles, hydration starts on surface of particles, hence, it might not be completely hydrated. This causes low strength and low durability.
10. Wet cement can cause severe skin burns if not washed off with water immediately.
Answer: a [Reason:] Cement is highly alkaline and setting process is exothermic. Wet cement is strongly caustic and causes skin burns. Similarly, dry cement causes eye or respiratory irritation, when it comes in contact with mucous membranes.
11. Green cement is:
a) Green coloured cement
b) Cement mixed with plant products
c) Cement mixed with recycled materials
d) Cement mixed with green algae
Answer: c [Reason:] Green cement is a cementitious material which employs the use of optimized recycled materials. These can meet or even exceed the functional performance of Portland cement.
12. What is the depth the needle in Vicat apparatus should penetrate into the cement paste in
a) 33-35 cm from bottom of mould
b) 33-35 mm from top of mould
c) 33-35 cm from top of mould
d) 33-35 mm from bottom of mould
Answer: b [Reason:] The best procedure has been clearly mentioned in IS 4031 Part 4. According to the code, 33-35mm depth of penetration is ideal.
1. Properties of concrete can broadly be divided into:
Answer: d [Reason:] Based on state of concrete, its properties vary. Concrete in fresh state has different properties than concrete in hardened state.
2. The accumulation of water on outer surface of concrete is:
Answer: b [Reason:] Bleeding can be good as well as bad for fresh concrete. Sometimes due to improper mixing, the water forms a thin layer on outer surface, by oozing out through voids.
3. Which of the below property of aggregates is not desirable?
a) Smooth texture
b) Well graded
c) Angular shape
d) Smaller size
Answer: c [Reason:] Aggregates should provide space for cement paste so as to lubricate the area. The parameters like texture, size, shape, grading are to be considered. Larger size, cubical, round and rough textured aggregates are preferred.
4. How does the strength of concrete differ with age of concrete?
c) No effect
d) Increases, then decreases
Answer: a [Reason:] It increases with increase in age. The strength measured after days, months and years shows an increase. It takes 28 days for concrete to attain full strength. However, it continues to attain strength even after 28 days.
5. Impermeability is a property of fresh concrete.
Answer: b [Reason:] Fresh concrete cannot be judged as impermeable. After it hardens and forms a structure, it may be impervious or pervious. Ideally it should be impermeable.
6. Permanent dimension changes due to loading is termed as:
Answer: c [Reason:] Concrete shrinks with age. The changes in dimension are called creep. It is determined using creep coefficient which is the ratio of ultimate creep strain to elastic strain at the age of loading.
7. Which admixture is used to improve workability?
Answer: a [Reason:] Plasticizers help to increase the workability of concrete without altering the water-cement ratio. It is very helpful as it provides the required workability, at the same time does not compromise on strength.
8. Workability reduces with time.
Answer: a [Reason:] The rate of evaporation of water from concrete mix increases as time increases. Loss of water leads to less workability.
9. Bleeding is good to an extent if it occurs when concrete is:
Answer: c [Reason:] While the concrete is still plastic, the accumulated water due to bleeding can be used to mix concrete again and improve workability. It also benefits by further reducing water-cement ratio.
10. M15 concrete is used for:
d) Mass concreting works
Answer: b [Reason:] M10 is used for Mass concrete works, dams, etc. M20 is used for R.C.C. structures. M15 can be used for ground floor construction also.
11. In design of R.C.C. structures, the tensile strength of concrete is taken as:
Answer: d [Reason:] Since concrete does not take up tensile loads, it is taken as zero. But IS 456-2000 recommends the tensile strength to be calculated using Ft = 0.7√fck N/mm2.
12. Higher the cement content,
a) Higher aggregates
b) Lower workability
c) Higher strength
d) Lower strength
Answer: c [Reason:] Higher the cement content i.e. lower the aggregate cement ratio, higher is the strength. It improves workability also.
1. The fineness modulus of sand lies in the range:
Answer: c [Reason:] Fineness modulus is an index number which represents average size of sand particles. It is calculated after conducting sieve analysis.
2. An ideal sand should comprise of which of the following grain types?
a) Cubical, fine
b) Angular, coarse
c) Round, coarse
d) Irregular, fine
Answer: b [Reason:] For sand to be used in every type of construction, the grains must suit all requirements. Angular, coarse grained sand is the one suitable for all work.
3. Sand in mortar helps in adjusting the strength requirements:
Answer: a [Reason:] The grade and amount of sane used in making mortar helps in adjusting strength parameter. It also helps in increasing resistance against crushing.
4. A sand is not said to be ideal if:
a) Chemically inert
b) Free from organic salts
c) Is soft
d) Contains silicon dioxide
Answer: c [Reason:] An ideal sand should be hard and not soft. It will be difficult to work with if it is soft.
5. Sands should pass through:
a) BIS 480 sieve
b) BIS 8 sieve
c) BIS 5 sieve
d) BIS 6 sieve
Answer: a [Reason:] The particle size of sand is between 4.75mm and 75 microns. BIS 480 sieve represents 4.75mm sieve opening.
6. Bulking of sand increase the strength of mortar.
Answer: b [Reason:] Bulking increases volume of mortar and not the strength. In fact it decrease the strength, leading to future cracks in the structure.
7. The solution used to test impurities in sand in field is:
a) Sodium sulphate
b) Sodium hydroxide
c) Sodium nitrate
d) Sodium chloride
Answer: b [Reason:] A small amount of sand is added to a solution of sodium hydroxide and stirred. If colour changes to brown, presence of impurity is detected.
8. What is the maximum percentage of silt allowed in sand to be used in concrete?
Answer: c [Reason:] If more silt content is present, it will lead to improper measurement of volume or weight. It should be washed off to bring it to allowable limit.
9. Which one of the below cannot to be used as a substitute of sand?
b) Quarry dust
Answer: b [Reason:] Surkhi is pieces of burned clay, M-sand is manufactured sand, glass can be powdered and these form excellent substitutes for sand. Quarry dust has flaky grains and is not recommended to use in concrete or masonry works, though it can be used for low strength works.
10. The density of wet sand is:
a) 1922 kg/m3
b) 1682 kg/m3
c) 1281 kg/m3
d) 1522 kg/m3
Answer: a [Reason:] 1682 kg/m3 is density of rammed sand, 1281 kg/m3 is density of dry sand and 1522 kg/m3 is of silica sand.
1. For a good building stone how much is the required crushing strength?
a) Less than 50 N/mm2
b) Greater than 100 N/mm2
c) 155 N/mm2
d) 10 N/mm2
Answer: b [Reason:] Crushing strength or compressive strength of a stone is the load per unit area at which the stone starts cracking. It should be greater than 100 N/mm2 to ensure sufficient strength for use in construction.
2. Which of the following is a good fire-resistant stone?
Answer: a [Reason:] Granite and Quartz undergo sudden expansion and flies into splinters. Limestone gets easily crumbled. Clay can withstand higher temperature and is used in pizza ovens, fireplaces, etc…
3. What is a freestone?
a) Stone free from impurities
b) Stone that doesn’t require dressing
c) Metamorphic stone
d) Stone free from veins and planes of cleavage
Answer: d [Reason:] For the ease of quarrying a stone must be soft, compact-grained, homogeneous, free from veins and planes of cleavage.
4. Why are stones with lighter shades of colour preferred?
a) Easy to clean
b) Easily available
c) Don’t spoil the appearance
d) Darker shades are heavier
Answer: c [Reason:] Even if the stone fades a little bit it will not show a striking difference and doesn’t spoil the look of it. They don’t need to be painted or maintained much compared to darker shades.
5. Hardness is an important parameter considered in the construction of:
Answer: c [Reason:] It’s required in structures subjected to heavy loading. Bridge is one such structure. Slabs, walls and arches are not subjected to heavy loadings as bridge.
6. What is the required specific gravity for a good building stone?
a) Greater than 2.7
b) Less than 3
c) Greater than 3
d) Less than 2.7
Answer: a [Reason:] As per IS standards. Heavy stones are used in construction of abutments, dams, docks. Lighter ones are used in building construction.
7. The percentage absorption by weight of a good stone, after how many hours should not exceed .6?
a) 6 hrs
b) 12 hrs
c) 48 hrs
d) 24 hrs
Answer: d [Reason:] As per IS standards, 24 hrs is the time a stone has to be immersed in water to check for water absorption. Time less or more than this would not result in providing the appropriate data.
8. What texture should a building stone possess?
a) Loose grains
b) Crystalline structure
Answer: b [Reason:] Texture is the grains composing the stone in the strata. Crystalline structure is the required texture. Other options are undesired textures.
9. Seasoning is required for stones.
Answer: a [Reason:] A stone should be properly dried before using for structural works. The sap contained in freshly quarried stones will make them soft and lead to decay eventually.
10. Toughness index of a good stone should be more than:
Answer: d [Reason:] Toughness is the ability to resist impact forces. A good building stone should have high toughness index to resist vibrations from machinery, moving loads, etc…
11. A percentage wear of 3% indicates a good stone.
Answer: b [Reason:] A percentage wear of less than 3% indicates a non-satisfactory stone. A percentage wear of 3% indicates a tolerable stone and greater than 3% indicates a good quality stone.
1. Aluminium is commercially produced from:
a) Aluminium sulphate
Answer: d [Reason:] Bauxite is the most commonly used ore of aluminium for production. It occurs as a weathering product of iron and silica.
2. By which of the below process is Aluminium manufactured?
a) Bayer process
b) Ostwald process
c) Mayer process
d) Haber process
Answer: a [Reason:] In Bayer process, alumina in bauxite is dissolved in caustic soda solution and precipitated to obtain aluminium hydroxide and calcinated to form pure Al2O3.
3. Which is the most important and useful alloy of Aluminium?
Answer: c [Reason:] Duralumin consists of 95% aluminium, 4% copper, 0.5% magnesium and 0.5% manganese. It is widely used in aircraft manufacturing due to its light weight and high strength.
4. Aluminium has a higher maintenance cost.
Answer: b [Reason:] Aluminium has excellent corrosion resistance and can withstand weathering, hot and humid conditions also. Hence, maintenance cost required is less.
5. Which of the following is a property of aluminium?
a) Hard material
c) Noise control
Answer: c [Reason:] Aluminium is an excellent reflector of electromagnetic and sound waves. Therefore, it is less affected by external noise compared to other building materials.
6. Aluminium appears greyish in colour in pure form.
Answer: b [Reason:] Pure form of Aluminium is white in colour. Its colour can vary from grey to yellow or light green depending on the presence of impurities. Yellow colour is imparted by Iron trichloride (impurity).
7. Aluminium finds its application in:
a) Golf clubs
b) Dehydrating agents
c) Waste management
d) Cricket field
Answer: a [Reason:] Compared to steel, aluminium is light weight. Aluminium golf heads, shafts allow golfers to swing faster and increase the ball’s distance with each shot.
8. What is the melting point of Aluminium?
Answer: b [Reason:] The boiling point of aluminium is 2470oC. It is strong and can be widely used everywhere.
9. Recycled Aluminium is called:
a) Primary Aluminium
b) Green Aluminium
c) Secondary Aluminium
d) Subsequent Aluminium
Answer: c [Reason:] Recycled Aluminium is called secondary aluminium and same properties of primary aluminium.