A highly charged piece of metal (with uniform potential throughout) tends to spark at places where the radius of curvature is small, or at places where there are sharp points. The breakdown electric field strength for air is about 3 × 106 V/m.(a) What is the maximum possible potential of a metal sphere of 2 cm radius in air? (That is, what is the potential at the surface of the sphere, relative to infinity?)(b) What is the maximum possible potential of a metal sphere of only 0.6 mm radius?