Find the flux of the electric field thruogh a spherical surface of radius R due to a charge of 10 to the power -7 at the center and another equal charge at a point 2R away from the center.

          

b) A charge  q is placed at the center of the open cylindrical vessel. the flux of electric field through the surface of the vessel is q/2 how can this be true. the two surfaces are not parallel plate conductor.