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