chapter 29 Flashcards
(69 cards)
is a round, three dimensional object, the surface of which is the same distance from the center in all directions.
sphere
is an elongated, closed curve with two foci.
ellipse
is earth a perfect sphere?
no, the equater is long than pole to pole
what are some of the ancient observations that tell us earth is a sphere
gravity,lunar eclipse,people in different parts of the world see different stars
is an area 15 degrees wide in which is the time is the same.
time zone
is a spinning of earth on its axis, each line drawn from earth’s north pole to it;a south pole.
rotation
is the motion of earth in an elliptical orbit around the sun.
revolution
is defined as the plane of earths orbit around the sun.
ecliptic
occurs when earths rotational axis is tilted directly toward the sun or away from the sun.
solstice
earths rotational axis is perpendicular to a line drawn from the center of earth to the center of the sun.
equinox
false, they are modified to fit around cities,states,and country borders, and other key sites
true or false? all time zones are the exact same size?
Babylonians
who devised a method of timekeeping around 300 B.C.?
Babylonians symbol for the sun
what was the symbol for degree taken from?
360 degrees
how many degrees does the earth spin in one hour?
24 hours
how many hours does it take the earth to make one full rotation?
15 degrees
how many degrees does the earth spin in one hour?
east
what direction does the sun rise?
west
what direction does the sun set?
24 total
how many time zones are there in the world?
east
which direction do you move to add hours to the time?
west
which direction do you move to subtract hours from the time?
6 time zones
how many time zones are there in the united states?
eastern time central time mountain time pacific time Atlantic/Atlanta time Hawaiian time
what are the names of the time zones?
when the sun is directly above us @noon till the next day its above us @noon (noon-to-noon)
what is a solar day?