NHPC-JE'21 CE: Daily Practices Quiz. 23-Dec-2021

Know your strengths and practice your concepts with this quiz on NHPC JE Recruitment 2021. This quiz for NHPC JE Recruitment 2021 is designed specially according to NHPC Syllabus 2021.

Quiz: Civil Engineering
Exam: NHPC-JE
Topic: Miscellaneous

Each question carries 1 mark
Negative marking: 1/4 mark
Time: 8 Minutes

Q1. Which of the following relation is/are used in deriving the relation between the flow rate and the pressure difference between the straight section and the throat of a venturi-meter that has no losses?
(a) ideal gas law
(b) Bernoulli and continuity equation
(c) Relation between friction factor and Reynolds number and Bernoulli equation
(d) Bernoulli equation

Q2. M-30 is considered as _________ type of concrete.
(a) Ordinary
(b) Standard
(c) High strength
(d) All of the above

Q3. If specific yield of particular sand is 30% and its porosity is 50%, then the specific retention of the sand will be
(a) 80%
(b) 55%
(c) 40%
(d) 20%

Q4. The ruling gradient for plain and rolling terrain is
(a) 3.3%
(b) 5%
(c) 6%
(d) 4 %

Q5. Efflorescence in bricks cause due to …………………
(a) excessive burning of bricks
(b) high porosity of bricks
(c) high silt content in brick earth
(d) soluble salts present in clay

Q6. In the design of purlins, depth of angle section should not be less than:
(a) L/45
(b) L/60
(c) L/50
(d) No relationship

Solutions

S1. Ans.(b)
Sol. For derive the relation between the flow rate and the pressure difference between the throat and straight section of a venturi meter we need continuity equation and Bernoulli’s equation both.

S2. Ans.(b)
Sol.

Concrete Grade	Type of concrete
M10 – M20	Ordinary
M25 – M55	Standard
M60 – M80	High strength

S3. Ans.(d)
Sol. Given,
Specific yield (S_y) = 30%
Porosity (n) = 50%
Specific retention (SR) =?
S_y+S_R=n
30%+S_R= 50%
S_R=20%

S4. Ans.(a)
Sol. The ruling gradient for plain and rolling terrain is 3.3% or 1 in 30 while for mountainous terrain it is 5% or 1 in 20.

S5. Ans.(d)
Sol. Defects in bricks-
Efflorescence→ This defect appears in bricks due to the presence of alkalis in the bricks.
Chuffs → This is the defect in bricks in which shape of the bricks gets deformed due to rain water falling on hot brick.
Bloating → Bloating of bricks is swollen spongy mass over the surface of burned bricks.
Black core→ The brick converts in black core because of improper burning.

S6. Ans.(a)
Sol. In the design of purlin, depth of angle section should not be less than L/45 and the width should not be less than L/60.