Quiz: Civil Engineering
Each question carries 1 mark
Negative marking: 1/4 mark
Time: 10 Minutes
Q1. Compression members always tend to buckle in the direction of the:
(a) Perpendicular to the axis of load,
(b) Minimum cross-section
(c) Least radius of gyration
(d) Axis of load
Q2. The factor of safety for steel as compared to concrete is ……………
(d) None of these
Q3. Consider the following statement regarding characteristic strength of concrete:
“the test result of the sample shall be the average of the strength of x specimens. The individual variation should not be more than ± Y% of the average.”
(a) 5, 15 respectively
(b) 5, 5 respectively
(c) 3, 5 respectively
(d) 3, 15 respectively
Q4. Calculate the seepage velocity of water through a permeable soil under a hydraulic gradient of 1/40. Take coefficient of permeability K = 1.2 × 10^(–2) m/s
(a) 48 × 10^(–2) m/s
(b) 3 × 10^(–4) m/s
(c) 33.3 × 10^(–2) m/s
(d) 4.8 × 10^(–4) m/s
Q5. The viscosity of a fluid with specific gravity 1.3 is measured to be 0.0034 N-sec./m². Its kinetic viscosity, in m²/s, is
(a) 2.6 × 10–6
(b) 4.4 × 10–6
(c) 5.8 × 10–6
(d) 7.2 × 10–6
Q6. If a ductile material is subjected to a unidirectional tensile force, then to avoid shear failure, the material should have its shear strength at least equal to
(a) its tensile strength
(b) Half the tensile strength
(c) Its compressive strength
(d) Twice the tensile strength
Q7. Plaster of Paris is obtained by calcining _
Q8. A relatively fixed point of known elevation above datum is called __.
Q9. To avoid an interruption in the flow of a siphon, an air vessel is provided __.
at the inlet
at the outlet
at the summit
at any point between the inlet and outlet
Q10. Workability of concrete for a given water content is good if the aggregates are
(a) Angular aggregates
(b) Flaky aggregates
(c) Rounded aggregates
(d) Irregular aggregates
Sol. Compression members always tends to buckle in the direction of the least radius of gyration.
Sol. factor of safety of steel ⇒1.15
Factor of safety of concrete ⇒ 1.5
→ Due to variability in strength of concrete due to poor quality control, poor workmanship etc., higher factor of safety is given for concrete in comparison to steel.
Sol. The test result of the sample shall be average of the strength of 3 specimens. The individual variation should not be more than ± 15% of the average.
Sol. Given i= 1/40, K= 1.2×10-2 m/sec.
Seepage velocity (v) = ki
= 3×10^(-4) m/sec
Sol. Given, Dynamic viscosity (μ)=0.0034 (N-sec)/m^2
Specific gravity (G)=1.3
G=(densityi of fluid(ρ))/(Density of water(ρω) )
▭(ρ=1300 kg\/m^3 )
Kinematic viscosity (ν)=(Dynamic viscosity (μ))/Density(ρ)
Sol. If ductile material is subjected to a unidirectional tensile force, then to avoid shear failure material should have its shear strength is twice the tensile strength.
Sol. Plaster is made by heating gypsum (〖CaSO〗(4.) 2H_2 O) powder, thus converting it to calcium sulphate hemihydrate (〖CaSO〗(4.) 1/2H_2 O). The hemihydrate is also known as stucco or Plaster of Paris.
Sol. A benchmark is a point of reference by which something can be measure. In surveying, a “bench mark” (two words) is a post or other permanent mark established at a known elevation that is used as the basis for measuring the elevation of other topographical points.
Sol. A syphon is a long-bent pipe used to connect two reservoirs at different levels intervened by a high ridge. The highest point of the syphon is called the summit. An air vessel is provided at the summit in order to avoid interruption in the flow.
Sol. Rounded aggregate has minimum percentage of voids hence provided more workability while flaky aggregate has maximum percentage of voids hence provided minimum workability.