Exercise 12.1

1. Name the following parts from the adjacent figure where 'O' is the centre of the circle.

(i) AO

Solution:

(ii) AB

Solution:

(iii) BC

Solution:

(iv) AC

Solution:

(v) DCB

Solution:

(vi) ACB

Solution:

(vii) AD

Solution:

(viii) shaded region

Solution:

2. State true or false.

i. A circle divides the plane on which it lies into three parts.

Solution:

TrueFalse

A circle divides the plane into parts: interior, exterior, and the circle itself.

ii. The region enclosed by a chord and the minor arc is minor segment.

Solution:

TrueFalse

A minor segment is the region between a and the .

iii. The region enclosed by a chord and the major arc is major segment.

Solution:

TrueFalse

A major segment is the region between a and the .

iv. A diameter divides the circle into two unequal parts.

Solution:

FalseTrue

A diameter divides the circle into two semicircles.

v. A sector is the area enclosed by two radii and a chord

Solution:

FalseTrue

A sector is the area enclosed by two and an , not a chord.

vi. The longest of all chords of a circle is called a diameter.

Solution:

TrueFalse

The is the longest chord as it passes through the .

vii. The mid point of any diameter of a circle is the centre.

Solution:

TrueFalse

Every diameter passes through the , so the midpoint of any diameter is the .