Given:
Given a circle with a chord of length = 10 cm = AB
Distance between centre to chord = 12 cm = OP
Concept:
The line perpendicular from the center to the chord bisects the chord.
Calculations:
From ΔAPO right-angled at P, Using Pythagoras theorem
AO2 = AP2 + OP2
AO2 = 52 + 122
⇒ AO = 13 cm = radius of the circle
The diameter of the circle = AO + OZ = 13 + 13 = 26 cm