Ch4

Question 1

T or F
Geographic coordinate systems are based on spherical coordinates and measured in latitude and longitude

Answer 1

T

Question 2

T or F
A geoid shifts the ellipsoid relative to the datum to achieve a best fit between the two

Answer 2

F
A datum shifts the ellipsoid relative to the geoid to achieve a best fit between the two

Question 3

Three Types of Projections are _____ , ____, and ______.

Answer 3

Azimuthal, cylindrical, conic

Question 4

Projections all distort one or more properties of
______ , ______, _______, and ________

Answer 4

distance, direction, shape, area

Question 5

T or F
UTM coordinate system breaks the world up into 6 zones of 60 degrees each

Answer 5

F
UTM coordinate system breaks the world up into 60 zones of 6 degrees each

Question 6

What is data called that has a defined coordinate system?

Answer 6

georeferenced

Question 7

Match the type of coordinate system to the definition:
Unprojected
Projected
Based on spherical coordinates
Converts spherical coordinates to planar coordinates

Answer 7

Unprojected (geographic)- Based on spherical coordinates
Projected- Converts spherical

Question 8

What type of coordinate system is measured in lat & long?

Answer 8

unprojected/geographic

Question 9

A _________, or GCS, stores locations in longitude-latitude values

Answer 9

geographic coordinate system

Question 10

An _______ is a smooth shape with a slightly smaller north-south axis

Answer 10

ellipsoid

Question 11

A ______ is a surface modeled from gravity differences and is closest to the true shape, but is too complicated for mapping

Answer 11

geoid

Question 12

A _______ shifts the ellipsoid relative to the geoid to achieve a best fit between the two.

Answer 12

datum

Question 13

A _____ optimizes the shift of geoid to ekkipsoid for the best fit at a particular location. It may also use a surveyed network of points to make further adjustments.

Answer 13

local datum

Question 14

A _____optimizes the fit for the entire earth btwn the geoid and ellipsoid.

Answer 14

geocentric or world-centered datum

Question 15

A datum definition includes what 2 things:

Answer 15

1. The particular ellipsoid used based on a determination of the earth’s major and minor axis
2. The adjustment or fit (translation of center)

Question 16

___is a mathematical conversion of points on the earth’s surface to a flat plane (map)

Answer 16

projection

Question 17

what are the 3 projection types?

Answer 17

cylindrical, conic, azimuthal

Question 18

Cylindrical projections usually preserve ______ and ______

Answer 18

direction and shape

Question 19

Conic projections usually preserve _____and/or _____

Answer 19

distance, area

Question 20

Azimuthal projections usually preserve ____and/or ______

Answer 20

area, distance

Question 21

How many standard parallels does a secant projection have?

Answer 21

2

Question 22

a common coordinate system for large-scale maps is?

Answer 22

UTM coordinate system, state plane CS

Question 23

Name one way the coordinate system used to store the data can impact the results of an analysis

Answer 23

areas or distances can be incorrectly calculated

Question 24

Proper alignment of data sets requires that each one have a label that records the complete coordinate system parameters
This label is called the ________

Answer 24

Spatial Reference

Question 25

The ______tool is used to permanently convert a data set from one coordinate system to another

Answer 25

Project

Question 26

________creates a new data set in the new coordinate system

Answer 26

projection

Question 27

Create the missing label for the true coordinate system of a map with the_____tool

Answer 27

Define Projection

Question 28

what tool Use only when CS is missing or incorrect?

Answer 28

define projection

Question 29

What tool should be used when changing a CS permanently?

Answer 29

project tool

Question 30

What tool is use to assemble collections of data with the same stored CS.

Answer 30

project tool

Question 31

The _______ of the data layer is the range of x-y coordinates of the features actually in the feature class.

Answer 31

extent

Question 32

Values between +180 and –180 indicate an ______GCS coordinate system with map units in degrees, whereas large values indicate a ______ coordinate system with units of feet or meters.

Answer 32

unprojected, projected

Question 33

What is is the selected x,y values and units for a map?

Answer 33

The coordinate space

Question 34

_________ measures east-west angles ___________ measures north-south angles above the equator

Answer 34

Longitude (X), from the Prime Meridian. Latitude (Y)

Question 35

____ are the basis for coordinate systems

Answer 35

Projections

Question 36

How can The coordinate system used to store the data impact the results of an analysis?

Answer 36

Areas or distances may be incorrectly calculated

Question 37

What units are determined by the coordinate system chosen for the map

Answer 37

Map units

Question 38

What units are the x-y values stored in the file

Answer 38

Stored units

Question 39

What is the name of the label that records the complete coordinate system parameters?

Answer 39

spatial reference

Question 40

What is the x-y precision in the spatial referencfe?

Answer 40

resolution