A cylindrical capacitor consists of a solid inner conducting core with radius 0.300cm , surrounded by an outer hollow conducting tube. The two conductors are separated by air, and the length of the cylinder is 13.5cm . The capacitance is 37.5pF.
A) Calculate the outer radius of the hollow tube.
B) When the capacitor is charged to 145V , what is the charge per unit length lambda on the capacitor?