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Types of Angles N

You are familiar with the directions used in geography. We
often use four main directions in our day-to-day lives: North
(N), South (S), East (E) and West (W). W E
We know that the Himalayan range is to the north, the
Indian Ocean is to the south, the Bay of Bengal is to the east
and the Arabian Sea is in the west of India.
Right Angle, Straight Angle and Complete Angle S

Study the following positions:

N N N

E E

S
We stand facing north.  1 By taking another quarter
Then take a quarter turn    1

4

4
clockwise to face east. This is turn   or ‘right-angle-turn’
also called a right-angle turn. we finally face south.
A right angle means 90°.
We observe that by turning two right angles from north, we face towards south. This is the same

as a half    1 + 1 = 1  turn. That means if
2
4
4
N N

S S
We stand facing north and take a half turn By another ‘straight-angle-turn’ from south,
 1 we face north again.
  clockwise, to face south. This is also

2
called a straight-angle turn.
A straight angle means 180°.

Turning by two straight angles (or four right angles) in the same direction makes a full turn. One
complete turn is called one revolution. The angle for one revolution is a complete angle, which
measures 360°.

N N

4 right-angle turns or 2 straight-angle turns make a complete angle of 360°

51 Lines and Angles