# Class 5 SST Chapter 1 Important Notes

Class 5 SST Chapter 1 Important Notes include key concepts related to the globe – a small model of the Earth from New Getting Ahead with Social Studies.

## The shape of the Earth

Long ago many people believed that the Earth is flat. It appears flat because it is very big. We can only see up to short distances.

In fact, it is a little flat on the poles and stretched at the center near the equator. So the shape is not perfectly round. The shape of the Earth is called the Geoid shape.

### How to study the Earth?

The size of the Earth is very large and if we want to study the Earth as a whole then it becomes very difficult. Globes and Maps are used to study the Earth.

### Definition of Globe

A globe is a small model of the Earth. It has a shape exactly like the Earth but small in size. It shows the shape and location of all the features like oceans, continents, countries, etc.

### Axis of the Earth

An imaginary line about which the Earth spins or rotates. It is called the axis of rotation.

This axis is not vertical. It is tilted at an angle of 23.5 degrees. The tilt of the axis is called obliquity.

### North and South Pole

The two endpoints of the axis of rotation are called the poles. The point in the North direction is called the North Pole and the point in the south is called the South Pole.

 The Axis of rotation, the tilt of the axis, and the poles.

### The Equator of the Earth

An imaginary line circling around the Earth at the center and divides the Earth into two equal halves is called the Equator.

Half of the Earth in the North is called the Northern Hemisphere.
Half of the Earth in the South is called the Southern Hemisphere.

### Latitudes or Parallels

Imaginary horizontal lines (circles) parallel to the Equator are called latitudes or parallels. Latitudes run from east to west.

Important Latitudes: (From north to south)
• North Pole – 90° N
• Arctic circle – 66.5° N
• Tropic of Cancer – 23.5° N
• Equator – 0°
• Tropic of Capricorn – 23.5° S
• Antarctic circle – 66.5° S
• South Pole – 90° S

#### Features of latitudes

• Latitudes are parallel to each other.
• Latitudes run from east to west direction.
• Latitudes are at equal distance from each other.
• Latitudes are complete circles except at the poles where they are just points.
• Latitude has maximum length at the Equator and decreases towards the poles.

### Longitudes or Meridians

The vertical lines (semi-circles) running between the poles are called longitudes or Meridians.

The vertical line passing through the Royal Observatory at Greenwich, London is taken as the reference ( 0°). It is called the Prime Meridian or the Greenwich Meridian.

#### Important Longitudes:

• Prime Meridian – 0°
• International Date Line – 180° E or 180° W

Both 180° E and 180° W meet at the same line. This line is called the International Date Line.

#### Feature of longitudes

• Longitudes are semicircles run between the poles from the north to south direction.
• Longitudes have the most space between them at the Equator and all the longitudes meet at the poles.

#### What is the Global Grid?

Latitudes and longitudes are perpendicular to one another. They cut each other at right angles and make the network of lines. This network is called the Global Grid.

The Global Grid is used to locate any place on Earth.
 Image by Clker-Free-Vector-Images from Pixabay