Q52 of 141 Page 447

Write T for true and F for false
(i) The degree measures of a semicircle is 180^o.

(ii) The perimeter of a circle is called its circumference.

(iii) A circle divides the plane into three parts.

(iv) Let O be the centre of a circle with radius r. Then a point P such that OP < r is called an interior point of the circle.

(v) A circle can have only a finite number of equal chords.

(i) T

(ii) T

(iii) T (The region inside the circle, region outside the circle and region on the circle).

(iv) T ( because point P lies inside the circle)

(v) F (A circle can have infinite number of chords)

The question consists of two statements, namely, Assertion (A) and Reason (R). For selecting the correct answer:

Assertion (A)	Reason (R)
A cyclic parallelogram is a square.	Diameter is the largest chord in a circle.

The question consists of two statements, namely, Assertion (A) and Reason (R). For selecting the correct answer:

Assertion (A)	Reason (R)
If two circles intersect at two points, then the line joining their centres is perpendicular to the common chord.	The perpendicular bisectors of two chords of a circle intersect at its centre.

Match the following columns:

Column I	Column II
(a) Angle in a semicircle measures	(p) 40^o
(b) In the given figure, O is the centre of a circle. If ∠AOB = 120°, then ∠ACB = ?	(q) 80^o
(c) In the given figure, O is the centre of a circle. If ∠POR = 90° and ∠POQ = 110°, then ∠QPR = ?	(r) 90^o
(d) In cyclic quadrilateral ABCD, it is given that ∠ADC = 130° and AOB is a diameter of the circle through A, B, C and D. Then, ∠BAC = ?	(s) 60^o

The correct answer is:

(a) – ……, (b) – ………,

Fill in the blanks

(i) Two circles having the same centre and different radii are called ________ circles.

(ii) Diameter is the _________ chord of a circle.

(iii) A continuous piece of a circle is called the ________ of the circle.

(iv) An arc of a circle is called a __________ if the ends of the arc are the ends of a diameter.

(v) A segment of a circle is the region between an arc and a ________ of the circle.

(vi) A line segment joining the centre to any point on the circle is called its ________.