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In Fig. if PQR is the tangent to a circle at Q whose centre is O, AB is a chord parallel to PR and ∠BQR = 70°, then ∠AQB is equal to

(A) 20° (B) 40° (C) 35° (D) 45°

Circles

In Fig. if PA and PB are tangents to the circle with centre O such that ∠APB = 50°, then ∠OAB is equal to

(A) 25° (B) 30° (C) 40° (D) 50°

Circles

In Fig.  if O is the centre of a circle, PQ is a chord and the tangent PR at P makes  an  angle  of  50°  with  PQ,  then ∠POQ is equal to

(A) 100° (B) 80° (C) 90° (D) 75°

Circles

At one end A of a diameter AB of a circle of radius 5 cm, tangent XAY is drawn  to  the  circle.  The  length  of  the  chord  CD parallel  to  XY  and  at  a distance 8 cm from A is

(A) 4 cm (B) 5 cm (C) 6 cm (D) 8 cm

Circles

From a point P which is at a distance of 13 cm from the centre O of a circle of radius 5 cm, the pair of tangents PQ and PR to the circle are drawn. Then the area of the quadrilateral PQOR is

(A) 60 cm² (B) 65 cm²       (C)  30 cm² (D) 32.5 cm²

Circles

In Fig. , AB is a chord of the circle and  AOC is its diameter such that  ∠ACB  =  50°.  If AT  is  the tangent to the circle at the point  A, then ∠BAT is equal to

(A) 65° (B) 60° (C) 50° (D) 40°

Circles

In  Fig. ,  if ∠AOB  =  125°, then ∠COD is equal to

(A) 62.5° (B) 45° (C) 35° (D) 55°

Circles

If radii of two concentric circles are 4 cm and 5 cm, then the length of each chord of one circle which is tangent to the other circle is
(A) 3 cm (B) 6 cm (C) 9 cm (D) 1 cm

Circles

In  Fig., PQ  is  a chord of a circle and PT is the tangent at P such that ∠QPT = 60°. Then ∠PRQ is equal to 

(A) 135° (B) 150° (C) 120° (D) 110°

Circles

In  Fig. ,  the  pair  of AQ drawn from an external point A to a circle with centre O are perpendicular to each other and length of each tangent is 5 cm. Then the radius of the circle is

(A) 10 cm (B) 7.5 cm (C) 5 cm (D) 2.5 cm