The chord of a circle of radius 10 cm subtends a right angle at its center. Find the length of the chord (in cm).

Question : The chord of a circle of radius 10 cm subtends a right angle at its center. Find the length of the chord (in cm). 

Doubt by Charu

Solution : 
OA = OB = r = 10 cm (Given)
∠ AOB = 90° (Given)

In Rt. ∆ AOB
By Pythagoras Theorem 
AB² = OA²+OB²
AB² = (10)²+(10)²
AB² = 2×(10)²
AB = √[2×(10)²]
AB = 10√10 cm