**Quiz: Civil Engineering**

**Exam: SSC-JE**

**Topic: Surveying**

**Each question carries 1 mark**

**Negative marking: 1/4 mark**

**Time: 10 Minutes**

Q1. Radiation, intersection and resection are

(a) Compass surveying techniques

(b) Chain surveying techniques

(c) Levelling techniques

(d) Plane table surveying techniques

Q2. The ratio of focal length of the objective to stadia interval is called

(a) additive factor

(b) multiplying factor

(c) staff intervals

(d) subtractive factor

Q3. A line of true length 500 m when measured by a 20 m tape is reported to be 502 m long. The correct length of the tape is

(a) 19.92 m

(b) 20.08 m

(c) 20.80 m

(d) 21 m

Q4. Contour interval is

(a) inversely proportional to the scale of the map.

(b) directly proportional to the flatness of ground.

(c) large for accurate works.

(d) None of these

Q5. In reciprocal levelling, the error which is not completely eliminated, is due to

(a) earth’s curvature

(b) non-adjustment of line of collimation

(c) refraction

(d) non-adjustment of the bubble tube

Q6. A series of closely spaced contour lines represents a

(a) steep slope

(b) gentle slope

(c) uniform slope

(d) plane surface

Q7. The error in the horizontal circle readings due to the line of collimation not being perpendicular to the trunnion axis is eliminated by

(a) taking readings on the different parts of horizontal circle

(b) taking readings on both the faces

(c) removing the parallax

(d) transiting the telescope

Q8. The direction of the magnetic meridian is established at each traverse station and the direction of the line is determined with reference to the magnetic meridian. This method of traversing is called

(a) fast needle method

(b) loose needle method

(c) bearing method

(d) fixed needle method

Q9.The fixed point whose elevation is known, is called :

(a) Benchmark

(b) change point

(c) reduced level

(d) Station

Q10.The shrunk ratio is expressed as :

(a) Shrunk length × original length

(b) Shrunk length + original Length

(c) Shrunk length / original length

(d) None of these

SOLUTIONS

S1. Ans.(d)

Sol. four techniques of plane table surveying.

(i) Radiation

(ii) Traversing

(iii) Intersection

(iv) Resection

S2. Ans.(b)

Sol. Multiplying factor is the ratio of focal length to the objective of stadia interval.

▭(K=f/i)

Where, K = multiplying factor

f = focal length

i = stadia interval

S3. Ans.(a)

Sol. true length of survey line (L) = 500 m.

Measured length of the line (L’) = 502 m.

True or designated length of the chain (l) = 20 m.

Actual/ incorrect length of chain (l’) =?

L×l=L^’×l^’

500×20=502×l^’

l^’=500/502×20

▭(l^’=19.92 m.)

S4. Ans.(a)

Sol. Contour interval is the vertical distance between two consecutive contours. It is inversely proportional to the scale of the map, time and money.

S5. Ans.(c)

Sol. Reciprocal levelling is the levelling between two widely separated points in which observation are made in both directions. It eliminates collimation and curvature error fully and refraction error partly.

S6. Ans.(a)

Sol. → Closely space contour lines ⇒ Steep slope

→ Apart contour lines ⇒ Gentle slope

→ equally spaced contour lines ⇒ Uniform slope

→ Straight parallel and equally spaced contour lines ⇒ Plane surface.

S7. Ans.(b)

Sol. the error in the horizontal circle readings due to the line of collimation can be eliminated by taking readings on both the faces.

S8. Ans.(b)

Sol. in the case of loose needle method, the direction of the magnetic meridian is established at each traverse station and the direction of the line is determined with reference to the magnetic meridian.

S9. Ans.(a)

Sol. Any station or point of known reduce level is known as bench mark. Government departments such as PWD, railway etc. are responsible for establishing permanent benchmarks.

S10. Ans.(c)

Sol. ▭(Shrunk ratio =(Shrunk length)/(Original length))