Chapter 1: Locating Places on the Earth
How do we find any place on our huge, round Earth, and why is it noon in one place and night in another? In this chapter we read maps, use the grid of latitudes and longitudes, and learn how time changes as we travel east or west.
In this chapter you will
- read the three components of a map
- locate places using latitude and longitude
- work out local time from longitude
- explain Indian Standard Time
Topics
- Maps and Their Components NCERT 1.1
A map is a drawing of a place on a flat surface; a globe is a round model of the Earth.
- Latitudes and Longitudes NCERT 1.2
Latitudes are parallel circles measured north and south of the Equator (0° to 90°).
- Local Time and Standard Time NCERT 1.3
The Earth turns 15° every hour: going east, local time is ahead; going west, it is behind.
Key words
- Map
- a drawing of a place on a flat surface
- Scale
- how map distance relates to real distance
- Equator
- the 0° line of latitude around the middle of the Earth
- Latitude
- how far a place is north or south of the Equator
- Longitude
- how far a place is east or west of the Prime Meridian
- Standard time
- one time used by a whole country or zone
Summary
- A map shows a place from above using a scale, directions and symbols.
- Latitudes and longitudes form a grid; two numbers give the exact location of any place.
- Earth turns 15° an hour, so time is ahead in the east and behind in the west.
- India follows one Indian Standard Time, based on 82.5°E, 5 h 30 min ahead of Greenwich.