Page 106 - SST Class 06

MERIDIANS OF LONGITUDE location. For example, Kohima in Nagaland and
Barmer in Rajasthan are located on the same
The horizontal lines on the globe are known as
latitude—26°N, but they are situated very far from
the latitudes. The vertical lines on it are known as each other. But when
the longitudes. Together they form the grid .
we say that Kohima is North Pole
North Pole
90º S
90º S
The meridians of longitudes are vertical lines that located at 26°N and s an 80º80º
70º70º
eri
join the two poles. All longitudes are of the same 96°E, it becomes 90º M ridi e di ns a 60º60º Prime Meridian Prime Meridian
M
90º
50º50º
90º
length. It was very difficult to ascertain how these clear that we are 80º80º 70º70º 40º40º 80º 90º
80º
30º30º
60º
60º 20º20º 60º60º 70º70º
longitudes should be talking only about 50º 40º 10º10º ParallelsParallels 40º 50º
50º
50º
40º
40º
30º
30º
30º
20º
20º 10º10º 0º0º 10º10º 20º20º 30º
Equator
numbered. So, there was a Kohima and not 10º10º Equator
20º20º
consensus among different Barmer. 30º30º
40º40º
Greenwich
Greenwich
countries that the West
Eas
West
ud e de N AN IA East t des Grid on the globe
Longi
Longitu
tudes tu it DI ID Longitudes
Longitudes
longitude passing through 40 º gi ng RI
40º
0º 60º 70º 80º 90
Lo on L ER ME M 20º 30º 40º 50º 60º 0º 80º 9 º 0º
7
30º 20º 10
Greenwich should be 1 10º 20º 30 40º 5 DIFFERENCE BETWEEN
30º 20º 1 º 0º 0º0º 0º
º
f f
o e o E E
Equator
named the Prime Meridian e n in Li L M IM RI PR P Equator LATITUDES AND LONGITUDES
and it should be given the
value of 0°. Meridians of longitude We can know the location of a place on the Earth
with the help of latitudes and longitudes. The
differences between latitudes and longitudes can
Info Bits be discussed as under :
Info Bits
q The British Royal Observatory is located at Latitudes Longitudes
Greenwich, near London. 1. Latitudes are 1. Longitudes are
q The maximum distance between any two horizontal lines. vertical lines.
meridians is at the Equator (about 111 km). 2. The length of 2. All longitudes are
q All latitudes and longitudes are imaginary lines latitudes decreases equal in length;
which enable us to understand the Earth better. towards the poles; they converge at
the longest being the poles.
The Prime Meridian divides the Earth into two the Equator and the
hemispheres—the Eastern Hemisphere and the smallest being the
Western Hemisphere . As there are 360 degrees in
two poles.
a circle, a total of 360 longitudes a drawn—180 in
the Eastern Hemisphere and 180 in the Western 3. Latitudes help us 3. Longitudes help us
Hemisphere. Therefore, the longitudes in the to know the to know the time
Eastern Hemisphere are marked (east) and those temperature of of a place.
E
in the Western Hemisphere are marked W (west). a place.
Interestingly, the longitude at 180 is the same line
from both sides, so it is not marked E or W. Quiz Time
Write True or False :
Activity
1. Longitudes help us to know the temperature of
Prepare a chart or model to show the heat zones of
the earth. a place. _______
2. The Prime Meridian divides the Earth into two
ASCERTAINING LOCATION OF A PLACE BY hemispheres. _______
LATITUDES AND LONGITUDES 3. All longitudes are of the same length. _______
Both of latitudes and longitudes help us to know 4. Equator is the most important latitude. _______
the position of a place. When we know the
latitude of a place, we cannot know its exact 5. We can see globes of different sizes. _______
Contemporary Social Science-6
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