Out of two concentric circles, the radius of the outer circle is 6 cm and the chord PQ of the length 10 cm is a tangent to the inner circle. Find the radius (in cm) of the inner circle.
Show answer & explanation
Correct answer: D
Explanation
The correct answer is option 4 i.e. .
Given that
The radius of the outer circle is 6 cm
The chord PQ of length 10 cm is tangent to the inner circle
PS = PQ/2 = 10/2 = 5 cm
In a triangle OPS,
OS2 = OP2 - PS2 = 62 - 52 = 36 - 25 = 11
OS = √11