GEO 401: Geographic Information Systems
Midterm Examination | 2026/2027 Edition
Course Code: GEO 401
Course Title: Geographic Information Systems
Academic Session: 2026/2027 Edition
Instructions: Read each question carefully and choose the correct answer. Correct answers and detailed
rationales are highlighted in green.
1. Which primary data model represents spatial features as discrete point, line, or polygon entities
using coordinate pairs?
A) Raster model
B) Vector model
C) Grid model
D) Voxel model
Rationale: The vector data model uses discrete coordinate geometry (points, lines, and polygons) to represent
distinct features with explicit boundaries on the Earth's surface.
2. What fundamental geographic data structure represents continuous phenomena by dividing
space into a regular grid of cells or pixels?
A) Raster data model
B) Topological vector model
C) Relational attribute table
D) Triangulated Irregular Network
Rationale: The raster data model represents continuous fields (such as elevation, rainfall, or temperature) using an
array of square grid cells or pixels, each holding a specific attribute value.
3. Which vector topology parameter explicitly defines which line segments connect at a shared
node or intersection?
A) Containment
B) Adjacency
C) Connectivity
D) Proximity
Rationale: Connectivity rules in GIS topology describe how arcs (lines) connect to each other at nodes, enabling
pathfinding and network flow modeling.
4. What mathematical model approximates the physical shape of the Earth to serve as the
reference surface for geographic coordinate systems?
, A) Sphere
B) Ellipsoid / Spheroid
C) Planar projection
D) Topographic surface
Rationale: Because the Earth bulges slightly at the equator due to rotation, an oblate ellipsoid (or spheroid) provides
the mathematical reference surface for computing geographical latitude and longitude.
5. The WGS 84 datum is defined primarily as a global datum because its origin point aligns with:
A) The Earth's center of mass (geocentric)
B) A local benchmark established at Greenwich, London
C) The average sea level recorded at the equator
D) A regional survey control point in North America
Rationale: World Geodetic System 1984 (WGS 84) is a geocentric datum whose origin is centered at the Earth's
center of mass, making it suitable for global GPS tracking.
6. Which map projection property preserves true relative areas of spatial features across the
entire map extent?
A) Conformal
B) Equivalent / Equal-area
C) Equidistant
D) Azimuthal
Rationale: Equivalent or equal-area map projections preserve correct area proportions, ensuring that regions of equal
size on the Earth maintain equal areas on the flat map surface.
7. A conformal map projection is specifically designed to preserve which geographic property
locally?
A) Angular relationships and local shape
B) True area scale ratios
C) Distance along all random lines
D) Direction from all map points to all other points
Rationale: Conformal projections maintain local angles and accurate shapes around small features by preserving a
constant scale in all directions at any given point.
8. What is the standard coordinate units used in the Universal Transverse Mercator (UTM)
projection system?
A) Decimal degrees
B) Arcseconds
C) Meters
D) Feet
Rationale: The UTM system projects the Earth into 60 longitudinal zones and uses meters as its standard linear unit
for Easting and Northing coordinates.
Midterm Examination | 2026/2027 Edition
Course Code: GEO 401
Course Title: Geographic Information Systems
Academic Session: 2026/2027 Edition
Instructions: Read each question carefully and choose the correct answer. Correct answers and detailed
rationales are highlighted in green.
1. Which primary data model represents spatial features as discrete point, line, or polygon entities
using coordinate pairs?
A) Raster model
B) Vector model
C) Grid model
D) Voxel model
Rationale: The vector data model uses discrete coordinate geometry (points, lines, and polygons) to represent
distinct features with explicit boundaries on the Earth's surface.
2. What fundamental geographic data structure represents continuous phenomena by dividing
space into a regular grid of cells or pixels?
A) Raster data model
B) Topological vector model
C) Relational attribute table
D) Triangulated Irregular Network
Rationale: The raster data model represents continuous fields (such as elevation, rainfall, or temperature) using an
array of square grid cells or pixels, each holding a specific attribute value.
3. Which vector topology parameter explicitly defines which line segments connect at a shared
node or intersection?
A) Containment
B) Adjacency
C) Connectivity
D) Proximity
Rationale: Connectivity rules in GIS topology describe how arcs (lines) connect to each other at nodes, enabling
pathfinding and network flow modeling.
4. What mathematical model approximates the physical shape of the Earth to serve as the
reference surface for geographic coordinate systems?
, A) Sphere
B) Ellipsoid / Spheroid
C) Planar projection
D) Topographic surface
Rationale: Because the Earth bulges slightly at the equator due to rotation, an oblate ellipsoid (or spheroid) provides
the mathematical reference surface for computing geographical latitude and longitude.
5. The WGS 84 datum is defined primarily as a global datum because its origin point aligns with:
A) The Earth's center of mass (geocentric)
B) A local benchmark established at Greenwich, London
C) The average sea level recorded at the equator
D) A regional survey control point in North America
Rationale: World Geodetic System 1984 (WGS 84) is a geocentric datum whose origin is centered at the Earth's
center of mass, making it suitable for global GPS tracking.
6. Which map projection property preserves true relative areas of spatial features across the
entire map extent?
A) Conformal
B) Equivalent / Equal-area
C) Equidistant
D) Azimuthal
Rationale: Equivalent or equal-area map projections preserve correct area proportions, ensuring that regions of equal
size on the Earth maintain equal areas on the flat map surface.
7. A conformal map projection is specifically designed to preserve which geographic property
locally?
A) Angular relationships and local shape
B) True area scale ratios
C) Distance along all random lines
D) Direction from all map points to all other points
Rationale: Conformal projections maintain local angles and accurate shapes around small features by preserving a
constant scale in all directions at any given point.
8. What is the standard coordinate units used in the Universal Transverse Mercator (UTM)
projection system?
A) Decimal degrees
B) Arcseconds
C) Meters
D) Feet
Rationale: The UTM system projects the Earth into 60 longitudinal zones and uses meters as its standard linear unit
for Easting and Northing coordinates.
