Page 186 - Maths Class 05
P. 186
Right Angle
An angle whose measure is 90° is called right angle .
ÐABC and ÐPQR are right angles.
P
A
O
B R
C
Obtuse Angle
An angle whose measure is more than 90° but less than 180° is called an obtuse angle .
ÐPQR and ÐKLM are obtuse angles.
P M
Q
R K L
Reflex Angle
An angle whose measure is greater than 180° is called reflex angle . The maximum an
angle can measure is 360°. It is measured from X to Z in anti-clock wise direction to get
reflex angle ÐXYZ.
X
Y
Z
Complete Angle
An angle that exactly measures to 360° is known as complete angle . Here the ray OA’
coincides OA after having a complete rotation. Hence ÐAOA’ = 360°.
A
O A'
Mathematics-5 186
