Exercise 4.6

Class 6 | Mathematics | Chapter 4| Basic Geometrical Ideas | Exercise 4.6

Question 1 : Take a circular sheet. Fold it into two halves. Crease the fold and open up. Do you find that the circular region is halved by the diameter? A diameter of a circle divides it into two equal parts; each part is a semi-circle. A semi-circle is half of a circle, with the end points of diameter as part of the boundary.

1. From the figure, identify :

(a) the centre of circle

(b) three radii

(c) a diameter

(d) a chord

(e) two points in the interior

(f) a point in the exterior

(g) a sector

(h) a segment

Answer 1 : (a) O is the centre.

(b) Three radii: OA, OB and OC

(c) A diameter: AC

(d) A chord: ED

(e) Interior points: O, P

(f) Exterior point: Q

(g) A sector: OAB

(h) A segment: ED

Question 2. (a) Is every diameter of a circle also a chord? (b) Is every chord of a circle also a diameter?

Answer 2 : (a) Yes, every diameter of a circle is also a chord.

(b) No, every chord of a circle is not a diameter.

3. Draw any circle and mark

(a) its centre

(b) a radius

(c) a diameter

(d) a sector

(e) a segment

(f) a point in its interior

(g) a point in its exterior

(h) an arc

Answer 3 :

(a) Center : O

(b) Radius = OA

(c) Diameter = AB

(d) Sector = COD

(e) Segment = DE

(f) O

(g) F

(h) AC

Question 4. Say true or false :

(a) Two diameters of a circle will necessarily intersect.

(b) The centre of a circle is always in its interior.

Answer 4 : (a) True

(b) True