I used the formula (E * Area * cos(theta)) and got the wrong answer (.02529) and I really don't understand why. I need help The square surface shown measures 4.0 mm on each side. It is immersed in a uniform electric field with magnitude E = 1930 N/C. The field lines make an angle of 35° with a normal to the surface, as shown. Take the normal to be "outward," as though the surface were one face of a box. Calculate the electric flux through the surface.