Karnataka Board Class 9 Maths Chapter 12 Circles Ex 12.1
Fill in the blanks : (Answers are filled)
(i) The centre of a circle lies in the interior of the circle, (exterior/interior)
(ii) A point, whose distance from the centre of a circle is greater than its radius lies in the exterior of the circle, (exterior/interior)
(iii) The longest chord of a circle is a diameter of the circle.
(iv) An arc is a semicircle when its ends are the ends of a diameter.
(v) Segment of a circle is the region between an arc and chord of the circle.
(vi) A circle divides the plane, on which it lies, in three parts.
2. Write True or False: Give reasons for your answers.
Line segment joining the centre to any point on the circle is a radius of the circle.
True. Each point in the circumference are equidistant from the centre of the circle. That distance is called radius of the circle.
A circle has only finite number of equal chords.
False. A circle has infinite number of equal chords because in a circle there are infinite points.
If a circle is divided into three equal arcs, each is a major arc.
False. If equilateral triangle is constructed in interior of the circle, the three equal parts are called minor arcs.
A chord of a circle, which is twice as long as its radius, is a diameter of the circle.
True. Diameter is a line segment which passes through centre of the circle.
Sector is the region between the chord and its corresponding arc.
False. The part which joins centre of the circle to the end points of arc, area coveted with two radii and arc s is called sector.
A circle is a plane figure.
True. A circle has two dimension.