i) A glass sphere of 2.20 mm diameter consists of a charge of + 1.70 nC. Determine what speed does an electron require to orbit the sphere 2.00 over the surface?
ii) The two 10 cm diameter charged disks face one other, 23 cm apart. Both disks are charged to - 80 nC. Determine the electric field strength at the mid-point among the two disks? Find out the electric field strength a point on the axis 5.0 cm from one disk among them?