Know your strengths and practice your concepts with this quiz on UPSSSC-JE Recruitment 2021. This quiz for UPSSSC-JE Recruitment 2021 is designed specially according to UPSSSC-JE Syllabus 2021.
Quiz: Civil Engineering
Each question carries 1 mark
Negative marking: 1/4 mark
Time: 8 Minutes
Q1. Find the hydraulic mean radius if a channel has a mean velocity of 2 m/s
Given : the silt factor is = 1 and channel is designed by Lacey’s theory
(a) 10 m
(b) 20 m
(c) 30 m
(d) 40 m
Q2. The length of a survey line when measured with a chain of 20 m nominal length was found to be 840.5 m. If the chain used is 0.1 m too long, the correct length of the measured line is:
(a) 844.7 m
(b) 845.7 m
(c) 846.7 m
(d) 847.7 m
Q3. In case of a direct Vernier scale–
(a) Smallest division is longer than smallest division of the main scale 1.
(b) Graduations increase in the same direction in which graduations of the main scale increases
(c) Graduations increase in opposite direction in which graduations of the main scale increase
(d) None of these
Q4. The magnetic bearing of a line is 50°30’ ad the magnetic declination is 4°30’ East. The true bearing of a line will be
Q5. The difference between face left and face right observation of a theodolite is 3’. The error is
Q6. Consider the following statements:
Reciprocal levelling eliminates the effect of
1. errors due to atmospheric refraction
2. errors due to earth’s curvature
3. errors due to line of collimation
4. mistake in taking levelling staff readings
Which of these statements are correct?
(a) 2, 3 and 4
(b) 1, 3 and 4
(c) 1, 2 and 3
(d) 1, 2 and 4
Sol. given, mean velocity (V)= 2m/sec
Silt factor (f)=1
Hydraulic mean radius (R) = 5/2 (V^2/f)
= 10 m.
Wrong length of measured line (L₁) = 840.5
Wrong length of chain (l₁) = 20.1 m
Correct length of chain (l) = 20 m
Correct length of measured line (L) = ?
L × l = L₁ × l₁
L × 20 = 840.5 × 20.1
L = (840.5 × 20.1)/20
Sol. In case of direct Vernier, graduation increase in the same direction in which graduations of the main scale increases.
True Bearing = Magnetic Bearing + Magnetic declination (East)
= 50°30’ + 4°30’
▭(Error=(Difference between face left and face right observation)/2)
Error = (3’)/2
Sol. Reciprocal levelling is used to determine the correct difference of elevations of two points. It eliminates the error due to curvature of earth, atmospheric refraction, and collimation error.