12-1B Longitude and Latitude

What is latitude?

What is longitude?

What is the prime meridian?

Coordinate Plane

How do you locate points on a coordinate plane?

Points are located using a set of ordered points, (x,y)

(3,4)

Coordinate System for a Sphere

A coordinate system used to locate a point on a sphere is similar to the coordinate plane. The system has two reference lines similar to the x and y axes.

The equator is one of these lines.

Lines that are parallel to the equator are called lines of latitude.

LatitudeLatitude is the distance north or south of the equator.

The equator is 0° latitude.

The North Pole is 90° north latitude (90°N).

The South Pole is 90° south latitude (90°S).

equator

Latitude

Prime MeridianThe prime meridian is a north-south reference line the runs

through England (Greenwich), continental Europe, and West Africa.

The prime meridian marks 0° longitude.

LongitudeLongitude is the distance east or west from the prime

meridian.

Other longitude lines range from 0° to 180°, east or west.

Longitude lines are all very long.

Look at the example on Page 757

Try It:Give the approximate latitude and longitude

of each city.1. Bombay, India2. Tokyo, Japan3. Sao Paulo, Brazil

1.18°N73°E

2.35°N,140°E

3.22°S,45°W

Earth InfoThe average radius of the earth is 3960 miles and its average circumference is approximately 24.900 miles.Times zones are based on the lines of longitude.The earth completes one counterclockwise rotation of 360° every 24 hours.Each 1-hour time zone corresponds to 15° of longitude.

15

24

360

Time Zones

Find the distance between the cities.Los Angeles, CA at 35°N latitude and New

York, NY at 41°N latitude.

The circumference of the earth is 24.900 miles.

The difference in latitude is 41°− 35°= 6°

24,900 times 6°/360°=415 miles

Find the distance between the cities.

Buenos Aires, Brazil at 35°S latitude and Sao Paulo, Brazil at 22°S latitude.

The circumference of the earth is 24.900 miles.

The difference in latitude is 35°− 22°= 13°

24,900 times 13°/360°= 899 miles

Find the distance between the cities.

What would you do if one of the latitudes is north and the other is south?

Add the degrees.

What is longitude?

Longitude is the distance east or west from the prime meridian.

What is latitude?

Latitude is the distance north or south of the equator.

What is the prime meridian?

The prime meridian is a north-south reference line the runs through England (Greenwich), continental Europe, and West Africa.

Assignment 12-1B

Page 759, 1-10, 19-25