In a circle centred at O, AB is a chord and C is any point on AB such that OC is perpendicular to AB. If the radius of the circle is 10 cm and OC = 6 cm, then the length of the chord is :

8 cm 12 cm 4 cm 16 cm

16 cm

We have, OA = 10 cm  OC = 6 cm In ΔAOC OA2 = OC2 + AC2 = 102 = 62 + AC2  = AC2 = 100 - 36 = AC2 = 64 = AC = 8 cm Now the length the chord = 8 × 2 = 16cm