Earth Flashcards
Shape of earth
Oblate spheroid OR
Ellipsoid
Diameter of Eq
6888nm
Diameter of poles
6865nm
Diameter of Eq > diameter of poles by how much
23nm
Compression ratio
0.3%
Rotation of earth viewed from North Pole
Anti clockwise
Rotation of earth viewed from South Pole
Clockwise
Earth rotatary direction
West to east
Inclination of the earth from orbital plane ie equatorial plane
66.5deg
Inclination of earth from normal plane or polar plane
23.5 deg
Graticule is a network bw ___ and ___
Latitude and longitude
How many gc drawn if 2 points NOT diametrically opp
1
How many gc drawn if 2 points diametrically opp
Infinite
Max longitude
Max latitude
180deg east/ west
90deg north/south
Great circle has ___ radius and ____ centre as that of the earth
Same radius and same centre
What is GC
Largest possible circle divides the earth into 2 equal halves
Gc gives ___ routes
Shortest
Radio signals follow ___
Gc path
GC example
Equator ,meridian and anti meridian
Small circle is ?
Any circle smaller than gc and doesn’t not divide earth into 2 equal halves
Small circle example
Parallels of latitude
Latitude ?
The angular distance measured along a meridian from the equator to a parallel of the latitude, measured in degrees, minutes, and seconds and named North or South.
Rhumb line /loxodrome
Regularly curved lines on earths surface which cuts all meridians at SAME ANGLE
Rhumbline gives
Constant true direction
RL distance >GC distance
True or false
True
RL position at poles
Spiral
Equator is gc and RL true or false
True
Geodetic lat >geocentric lat
True or false
True, geodetic or geographic lat is greater than geocentric
Max diff bw geodetic and geocentric is @
45deg latitude; 11.6min
Cardinal pts
0 or 360 deg
90deg
180deg
270deg
Quadrantal points
45deg (NE)
135deg(SE)
225deg(SW)
315deg(NW)
On real earth , GC and RL
GC- straight lines 
RL - curved line
On paper , GC and RL
RL- straight line
GC -curved line
Only ____ is a semi GC
Meridian