The electric field is measured all over the surface of a cylinder whose diameter is 8 cm and whose height is 20 cm, as shown in the diagram. At every location on the surface the electric field points in the same direction (+y). E1 is found to be 558V/m; E2 is 773V/m; E3 is 1233V/m.
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How much charge is inside the surface? E0 = 8.85e-12 C2/N m2.