Lecture 2 Flashcards
1
Q
Why do we need georeferencing?
A
Navigation, real estate, emergency, courier, market
2
Q
What is georeferencing?
A
Associating physical map or raster image with spatial locations
3
Q
Georeferencing and GIS?
A
Important to have a common frame of reference(projection) between the different layers so that the data(layers) can be related to each other
4
Q
Representative fraction? (RF)
A
Ration of distance on the map to distance on the ground
Ex) 1cm=1km –> 1cm=100,000cm –> 1:100,000 (RF)
5
Q
What is a geoid?
A
- Equipotential surface of earth’s gravity that most closely approximates the sea level of the ocean
- Shape of the surface of the Earth’s oceans would take under the influence of Earth’s gravitation and rotation alone
6
Q
Orthometric height?
A
- Height above sea level
- Height above an imaginary surface called the geoid
7
Q
Geodetic longitude? (lamda)
A
The angle between the prime meridian an the meridian passing through the point
8
Q
Geodetic Latitude?
A
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