Intro Flashcards
What is a great circle?
A circle around the world, the plane of which passes through the centre of the earth.
What is a meridian?
Half of a great circle, passing from pole to pole.
How is a position given?
A position is give in degrees minutes and decimals of latitude north or south and then degrees, minutes and decimals of longitude east or west.
Define latitude.
Latitude is the angle at the centre of the earth from the equator north or south to the observers position.
What is the Equator?
The equator is 0 degrees latitude.
What is a parallel of Latitude?
A small circle of latitude parallel to the equator.
Define longitude?
Longitude is the minor angle at the pole measured east or west from the prime meridian.to the observers meridian.
What is d’lat?
D’lat is the difference of latitude from one parallel of latitude to another.
How do you find d’lat?
If the latitudes are in the same direction from the equator, subtract them to find the d’lat. If they are in different directions add them to find d’lat. It is named north or south according to direction of travel.
What is d’long?
D’long is the difference of longitude from one meridian to another.
How do you find d’long?
If longitudes are in the same direction form the prime meridian, subtract them to get d’long. If they are in different directions, add them. If the value is greater than 180, subtract from 360 to get the minor angle. It is named east or west according to direction of travel.
What is 1 nautical mile equal to?
1 minute of latitude
What is the maximum latitude?
90 degrees
What is the maximum longitude?
180 degrees
Describe a Mercator chart.
A Mercator chart is a chart where the latitude and longitude lines are perpendicular to each other. It is as if the globe was projected onto a cylinder.
