GATE-GE SERIES
Geographic-information-system

General Science

26 previous year questions.

Volume: 26 Ques
Yield: High

High-Yield Trend

26
2025

Chapter Questions
26 MCQs

01
PYQ 2025
medium
geographic-information-system ID: gate-ge-

In supervised digital image classification, the number of combinations to be evaluated to select three best bands out of five bands is _____________

02
PYQ 2025
medium
geographic-information-system ID: gate-ge-

Piecewise linear contrast stretch is performed on an 8-bit image. The output ( ) would be zero for input value . The output ( ) would be 255 for . For the remaining input values, . If , then is_____________

03
PYQ 2025
medium
geographic-information-system ID: gate-ge-

In levelling between two points P and Q on opposite banks of a river, the level was set up near P, and the staff readings on P and Q were 2.165 m and 3.810 m, respectively. The level was then moved and set up near Q and the respective staff readings on P and Q were 0.910 m and 2.355 m. The true difference of level between P and Q is ____________m (rounded off to 3 decimal places).

04
PYQ 2025
medium
geographic-information-system ID: gate-ge-

A level with the height of the instrument being 2.550 m has been placed at a station having a Reduced Level (RL) of 130.565 m. The instrument reads 3.665 m on a levelling staff held inverted at the bottom of a bridge deck. The RL of the bottom of the bridge deck is _____________

05
PYQ 2025
medium
geographic-information-system ID: gate-ge-
A point is specified along the Greenwich Meridian at N latitude on an ellipsoid. The parameters of the ellipsoid are semi-major axis m and flattening factor . The volume of the ellipsoid is given by , where is the semi-minor axis. The latitude of the point on the sphere whose volume is the same as the volume of the ellipsoid of reference is \rule{2cm}{0.15mm} N (rounded off to 2 decimal places).
06
PYQ 2025
medium
geographic-information-system ID: gate-ge-
The scattering matrix for a fully polarimetric synthetic aperture radar pixel is given below. The element of the covariance matrix computed with a window will be __________ ? (rounded off to 2 decimal places).

Here, .

07
PYQ 2025
easy
geographic-information-system ID: gate-ge-

Figure below shows the scatterplot of training pixels of water (w), sand (s), forest (f) and commercial (c) in bands 1 and 2. Pixel ‘A’ having digital number 4 and 6 in band 1 and band 2, respectively, is to be classified using k-nearest neighbor classifier having the value of k equal to 5. The assigned class for the pixel ‘A’ is ____________

1
forest
2
sand
3
water
4
commercial
08
PYQ 2025
medium
geographic-information-system ID: gate-ge-

The figure below shows a one-dimensional function, , and a filter . Consider is padded with zeros on both sides. Which one among the following will be the final convolution output of with after the padding zeros are removed from the output?

1

2

3

4

09
PYQ 2025
medium
geographic-information-system ID: gate-ge-

In supervised digital image classification, the number of combinations to be evaluated to select three best bands out of five bands is ____________ (Answer in integer).

10
PYQ 2025
medium
geographic-information-system ID: gate-ge-

Piecewise linear contrast stretch is performed on an 8-bit image. The output ( ) would be zero for input value . The output ( ) would be 255 for . For the remaining input values, . If , then is __________ (Answer in integer).

11
PYQ 2025
medium
geographic-information-system ID: gate-ge-

In levelling between two points P and Q on opposite banks of a river, the level was set up near P, and the staff readings on P and Q were 2.165 m and 3.810 m, respectively. The level was then moved and set up near Q and the respective staff readings on P and Q were 0.910 m and 2.355 m. The true difference of level between P and Q is __________ m (rounded off to 3 decimal places).

12
PYQ 2025
medium
geographic-information-system ID: gate-ge-

A level with the height of the instrument being 2.550 m has been placed at a station having a Reduced Level (RL) of 130.565 m. The instrument reads 3.665 m on a levelling staff held inverted at the bottom of a bridge deck. The RL of the bottom of the bridge deck is __________ m (rounded off to 3 decimal places).

13
PYQ 2025
medium
geographic-information-system ID: gate-ge-

A point is specified along the Greenwich Meridian at N latitude on an ellipsoid. The parameters of the ellipsoid are semi-major axis m and flattening factor . The volume of the ellipsoid is given by , where is the semi-minor axis. The latitude of the point on the sphere whose volume is the same as the volume of the ellipsoid of reference is __________N (rounded off to 2 decimal places).

14
PYQ 2025
medium
geographic-information-system ID: gate-ge-
The statements below show the relationship of Whole Circle Bearing (WCB) with the Quadrantal Bearing (QB) for quadrant designations North-East (N-E), North-West (N-W), South-East (S-E) and South-West (S-W). Which of the following statements is/are correct?
1
For the quadrant S-W, QB = WCB −180°
2
For the quadrant S-W, WCB = 180° − QB
3
For the quadrant N-W, WCB = 180° − QB
4
For the quadrant N-W, QB = − WCB + 360°
15
PYQ 2025
medium
geographic-information-system ID: gate-ge-

In the figure below, and are the two instrument stations. The instrument stations and the object lie in the same vertical plane. Assume all instruments and staff are levelled.

= horizontal distance between the object and the station
= horizontal distance between the instrument stations
= staff reading at the Benchmark (BM) for horizontal line of sight
= reading on the staff at
= height of the point sighted by instruments at the staff kept at from the line of sight of the instruments
and = vertical angles to the reading on staff at from and , respectively

Which one of the following relationships is correct for ?


1

2

3

4

16
PYQ 2025
medium
geographic-information-system ID: gate-ge-
Given , where is the ellipsoidal/geodetic height at point , is the orthometric height and is the geoid undulation along the ellipsoidal normal. Which one of the following statements is correct?
1
Two points on the Earth’s surface that have the same ellipsoidal height will be on the same equipotential surface
2
The geoid undulation is the separation of the equipotential surface at the ground surface with respect to the ellipsoid
3
The points on an equipotential surface will not have the same orthometric height
4
The orthometric height of the instantaneous sea level is zero
17
PYQ 2025
medium
geographic-information-system ID: gate-ge-

In a closed traverse PQRST the following data were collected in the field. What is the correct sum of deflection angles for this traverse?

LineLength (m)Bearing
PQ201.5462°42'
QR189.68154°54'
RS231.94202°32'
ST272.55281°44'
TP256.8322°00'

1

2

3

4

18
PYQ 2025
medium
geographic-information-system ID: gate-ge-

Figure below shows an open traverse PQRS, where P is the starting point of traverse and S is the end point of traverse. Which one of the following is correct?

1
, ,
2
, ,
3
, ,
4
, ,
19
PYQ 2025
medium
geographic-information-system ID: gate-ge-

Two positions on the Earth’s surface are given in the form of Cartesian coordinates in the WGS84 reference frame and ellipsoid. The norm of difference of these two position vectors is the ____________

1
spherical distance
2
ellipsoidal distance
3
Euclidean distance
4
planar distance
20
PYQ 2025
medium
geographic-information-system ID: gate-ge-

The scattering matrix for a fully polarimetric synthetic aperture radar pixel is given below. The element of the covariance matrix computed with a window will be __________? (rounded off to 2 decimal places).

Here, .

21
PYQ 2025
medium
geographic-information-system ID: gate-ge-
In a closed traverse with five sides, the closing error found from the fore bearing and back bearing of the last line is . The correction to the fourth line will be:
1

2

3

4

22
PYQ 2025
medium
geographic-information-system ID: gate-ge-
When conducting a survey using a total station, a zenith angle is measured as in the direct mode. What is the equivalent zenith angle in the reverse mode?
1

2

3

4

23
PYQ 2025
medium
geographic-information-system ID: gate-ge-
Which of the following statements is/are correct in the context of Voronoi polygon?
1
A Voronoi polygon may contain more than one point, especially where the density of points is higher
2
The center of a Voronoi polygon is a circumcenter of a Delaunay triangle
3
Each intersection of Voronoi edges belongs to at least three Voronoi polygons
4
Voronoi polygons and Delaunay triangles are geometric dual of each other
24
PYQ 2025
medium
geographic-information-system ID: gate-ge-
In a plane triangle, the observed angles and , assumed uncorrelated, with given weights are:


The most probable values of these angles will be given by:
1

2

3

4

25
PYQ 2025
medium
geographic-information-system ID: gate-ge-

In a given weighted graph shown below, what is the value of the expression , where:
[i.] Alphabets A, B, C, D, E, and F denote the nodes
[ii.] Numbers 1 to 6 denote the weights between two nodes
[iii.] = shortest distance between node A and node E
[iv.] = number of paths with distance

1
100
2
64
3
81
4
121
26
PYQ 2025
medium
geographic-information-system ID: gate-ge-
For the weighted least squares adjustment, which of the following statements is/are correct?
1
Weighted sum of the squares of the residuals is minimized
2
The expected value of the residuals is equal to zero
3
Redundancy of observations is maximized
4
Weights are taken inversely proportional to the variance of the observations