Earths Dimensions

Question 0

Evidence of the shape of earth

Answer 0

Ships disappear past the horizon
Earths shadow on the moon during a lunar eclipse
Time differences between distant places
Altitude of stars change (Polaris-North Star)
-cannot be seen in the Southern Hemisphere
Photographs from space is our best piece of evidence

Question 1

Oblate spheroid

Answer 1

When diameter of equator is larger than polar diameter, slightly bulging in the middle due to rotation of earth

Question 2

Spheres of earth

Answer 2

Lithosphere- solid
Hydrosphere- water
Atmosphere- gases

Question 3

Lithosphere

Answer 3

Solid part of earth
Includes: crust and upper mantle
         ,      Bedrock
                Continents
                Ocean floor

Question 4

Hydrosphere

Answer 4

Water on earth
Includes: oceans
                Lakes
                Rivers
                Ground water
Approximately 75% of earths surface is covered with water

Question 5

Atmosphere

Answer 5

Shell of gases that surrounds earth

Divided into layers based on composition and temperature

Question 6

Troposphere

Answer 6

Layer closest to earths surface
Most important layer
Contains all elements necessary for life where weather takes place

Question 7

Latitude and longitude

Answer 7

In order to know where we are of earth we can use a coordinate system
Coordinate system- a method of locating points by labeling them with numbers called coordinates
Coordinates we are going to discuss latitude and longitude

Question 8

Latitude

Answer 8

The equator is 0 degrees
The North Pole is 90 degrees north
The South Pole is 90 degrees south
Latitude are circles parallel to the equator
Lines of latitude are the y coordinates of a map grid
Latitude is the angular distance north or south of the equator
Polaris is a distant star that is located almost exactly over earths North Pole and is almost exactly in line with its axis of rotation
In the northern hemisphere the altitude of Polaris is equal to the observers latitude

Question 9

Longitude

Answer 9

X coordinates on earths grid
Lines of longitude are also called meridians or great circles
Zero degrees longitude is called the prime meridian
It runs through Greenwich, England
Longitude lines represent the degrees of a circle east or west of the prime meridian
Latitude lines are parallel, longitude lines come together
Every degree is made up of 60 minutes
Every minute is made up of 60 seconds

Question 10

Time zones

Answer 10

There are 24 time zones
One time zone is for each hour of the day
Each time zone is assigned to one particular longitude
Each time zone is 15 degrees from the next
This is because the earth rotates 15 degrees per hour
If u travel west you are in an earlier time zone
If you travel east you r in a later time zone

Question 11

Local time

Answer 11

If you know ur longitude and the time at the prime meridian you can find ur local time

Steps
Calculate the difference from your location and the prime meridian
Divide by 15- this is the difference in hours
If you are east of the prime meridian, add the hours to get to your local time
If you are west of the prime meridian subtract the hours of your local time