GIS Map Projections and Datums 2

Question 1

Which map projection is used as the basis for the Universal Transverse Mercator (UTM) coordinate system?

Accepted Answer

Transverse Mercator

Answer

UTM is based on the Transverse Mercator projection, applied in 60 narrow north-south zones to minimize distortion.

Question 2

What does a 'false easting' value accomplish in a projected coordinate system?

Accepted Answer

It shifts the origin eastward to keep all X coordinates positive

Answer

A false easting offsets the X-axis origin so that all easting values within the zone are positive, avoiding negative coordinates.

Question 3

The Mollweide projection preserves which property?

Accepted Answer

Equal area

Answer

Mollweide is a pseudocylindrical equal-area projection often used for world maps showing global distributions.

Question 4

Which datum is used by the GPS satellite system as its native reference frame?

Accepted Answer

WGS84

Answer

GPS satellites broadcast positions referenced to WGS84, the World Geodetic System of 1984.

Question 5

A map projection that correctly represents the shape of small areas but distorts size is called:

Accepted Answer

Conformal

Answer

Conformal (orthomorphic) projections preserve local angles and shapes but distort areas, especially far from the standard line.

GIS - Geographic Information System Practice Test