Levelling & Contouring in Surveying Important Question for GATE

Civil Engineer Academy

Levelling & Contouring in Surveying Important Question for GATE

Leveling & Contouring in Surveying Important Question for GATE

Levelling & Contouring in Surveying Important Question for GATE navigating the examination demands a solid foundation in surveying techniques like levelling and contouring. Join us as we delve into a crucial set of questions, empowering you to confidently tackle these concepts and excel in your preparations.

one mark question

Q 1) The staff reading taken on a workshop floor using a level is 0.645 m. The inverted staff reading taken to the bottom of a beam is 2.960m. The reduced level of the floor is 40.500 m. The reduced level (expressed in m) of the bottom of the beam is

(a) 44.105
(b) 43.460
(c) 42.815
(d) 41.145

[GATE-2016 SET-I]

Q 2) In a levelling work sum of the back sight (BS) and FS have been found to be 3.085 m and 5.645 m respectively. If the reduced level (RL) of the starting station is 100m, the RL (in m) of the last station is_________?

[GATE-2015 SET-II]

Q 3) The combined correction due to curvature and refraction (in m) for a distance of 1 km on the earth surface of earth is

(a) 0.0673
(C) 7.63
(b) 0.673
(d) 0.763

[GATE-2015 SET-II]

Q 4) The Reduced Levels (RLs) of the points P and Q are +49.600m and +51.870m respectively. Distance PQ is 20m. The distance (in m from P) at which the +51.000 m counter cuts the line PQ.

(a) 15.00
(c) 3.52
(b) 12.33
(d) 2.27

[GATE-2014 SET-I]

Q 5) Which of the following errors can be eliminated by reciprocal measurements in differential levelling?

I. Error due to earth's curvature
Il. Error due to atmospheric refraction

(a) Both I and I|
(b) I only
(c) Il only
(d) Neither I nor Il


Q 6) Curvature correction to a staff reading in a differential levelling survey is

(a) always subtractive
(b) always zero
(c) always additive
(d) dependent on latitude


Q 7) If the distance between the instrument station and staff station is 1km, the correction for refraction in 'm' is

(а) 0.0673
(c) 0.0112
(b) 0.0785
(d) 0.0121


Q 8) The rise and fall method provides an arithmetic check on

(a) back sights and fore sights
(b) intermediate sights
(c) back sights and intermediate sights
(d) back sights, intermediate sights and fore sights


Q 9) While levelling in an undulating terrain, it is preferable to set up the instrument on

(a) the top of summit
(b) the bottom of a valley
(c) one side of the slope
(d) a flat location

[GATE 1992]

two marks questions

Q 10) A level instrument at a height of 1.320 m has been placed at a station having a reduced level
(RL) of 112.565 m. The instrument reads - 2.835 m on a levelling staff held at the bottom of a bridge deck. The RL (in m) of the bottom of the bridge deck is

(а) 116.720
(b) 116.080
(c) 114.080
(d) 111.050

[GATE-2018, SHIFT-I]

Q 11) An observer standing on the deck of a ship just sees the top of a lighthouse. The top of the lighthouse is 40m above the sea level and the height of the observer's eye is 5m above the sea level. The distance (in km. up to one decimal place) of the observer from the lighthouse is________?

[GATE-2017 SET-II]

Q 12) Two pegs A and B are fixed on opposite bank of 50 m wide river. The level was set up at A and staff reading on peg A and B were observed as 1.350 and 1.55 m respectively. Thereafter the instrument was shifted and set at B. The staff reading on Pegs B and A were observed as 0.75 and 0.55m respectively. If R.L of Peg A is 100.2 m the RL of Peg B (in m).______?

[GATE-2015 SET-II]

Q 13) A levelling is carried out to establish the reduced level (RL) of point R with respect to the bench mark (BM) at P. The staff reading taken are given below

Staff StationBSISFSRL
Q- 0.950-- 1.500-
If RL of P is + 100 m then RL (m) of R is

(a) 103.355
(b) 103.155
(c) 101.455
(d) 100.355

[GATE 2014 SET-I]

Q 14) A theodolite is set up a station A and 3 m long staff is is held vertically at station B. The depression angle reading at 2.5 m marking on the staff is 6°10'. The horizontal distance between A and B is 2200 m. Height of instrument at station A is 1.1 m and R.L of A is 880.88 m. Apply the curvature and refraction correction, and determine the R.L of B (in m).______?


Q 15) A bench mark has been established at the soffit of an ornamental arch at the known elevation of 100.0 m above mean sea level. The back sight used to establish height of instrument is an inverted staff reading of 2.105 m. A forward sight reading with normally held staff of 1.105 m is taken on a recently constructed plinth. The elevation of the plinth is

(a) 103.210 m
(b) 101.000 m
(c) 99.000 m
(d) 96.790 m


Q 16) Consider the following statements :

Assertion (A) : Curvature correction must be applied when the sights are long.
Reason (R): Line of collimation is not a level line but is tangential to the level line.

Of these statements, which one is correct?

(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true but R is not the correct explanation of A
(C) A is true but R is false
(d) A is false but R is true


Q 17) A light house of 120 m height is just visible above the horizon from a ship. The correct distance (m) between the ship and the light house considering combined correction for curvature and refraction, is

(a) 39.098
(b) 42.226
(c) 39098
(d) 42226


Q 18) The following measurements were made during testing a levelling instrument.

Instrument atStaff reading at P1Staff reading at Q1
P2.800 m1.700 m
Q2.700 m1.800 m

P, is closed to P and Q, is closed to Q. If the reduced level of station P is 100.000 m, the reduced level of station Q is

(a) 99.000 m
(b) 100.000 m
(c) 101.000 m
(d) 102.000 m


Q 19) During a levelling work along a falling gradient using a Dumpy Level and a Staff of 3 m length, following successive readings were taken 1.785, 2.935, 0.360, 1.320. What will be the correct order of booking these four readings in a level book? (BS: Back Sight, IS : Intermediate Sight, FS : Fore Sight)

(a) BS, FS, BS, FS
(b) BS, IS, FS, FS
(c) BS,IS, IS, FS
(d) BS, IS, BS, FS


Q 20) Consider the following figure, which is an extra from a contour map (scale = 1:20,000) of an area. An alignment of a road at a ruling gradient of 4% is to be fixed from the point O and beyond. What should be the radius of the arc with O as the centre to get the point of alignment of the next contour on the map?

Contour map

(a) 0.025 cm
(b) 0.25 cm
(c) 2.5 cm
(d) 5.0 cm


Q 21) A Bench Mark (BM) with Reduced Level (RL) = 155.305 m has been established at the floor of a room. It is required to find out the RL of the underside of the roof (R) of the room using Spirit Levelling. The Back Sight (BS) to the BM has been observed as 1.500m whereas the Fore Sight (FS) to R has been observed as 0.575 m (Staff held inverted). The RL(m) of R will be

(a) 155.880
(b) 156.230
(c) 157.380
(d) 157.860


Q 22) The staff reading at a distance of 80m from a level with the bubble at its centre is 1.52 m and when the bubble I moved 5 divisions out of the centre, the reading is 1.6 m the angular value of 1 division of bubble is

(a) 20.62 sec
(c) 14.53 sec
(b) 41.25 sec
(d) 25.05 sec


Q 23) A line of levels has been run from a bench mark of elevation 23.47 m and ends at another benchmark of elevation 23.50m. The sum of the Backsights is 16.26 m and that of the Foresights is 16.29m. The closing error is__________?


To understand all the fundamental regarding Surveying do visit the following Category.

To understand all about the fundamental concept of surveying do visit the following Article.

To understand all about the Scale, Types Of Scale And Accuracy & Errors In Surveying do visit the following link.

To understand all about the Chain Surveying: The Fundamental For Linear Measurement do visit the following link.

To understand all about the Correction In Chaining/Taping And Ranging In Surveying do visit the following link.

Leave a comment