Example 1 The voltage applied to a coaxial cylindrical electrode system (one core cable) dimensioned according to the most convenient arrangement in terms of puncture resistance is U=150 kV. Since the inner cylinder radius is r1 = 1 cm. a) Find the outer cylinder Radius, b) What is the minimum Ed force of the insulator to prevent puncture? c) If the Ed value of the insulator is 60 kV/cm, calculate the maximum voltage value that can be applied without puncturing the system. " 3 12