Solving a problem in physics section 67 point 90 electr

90. An electrostatic field is created by two infinite parallel planes charged by uniformly opposite charges with a surface density of σ1 = 1 nC / m2 and σ2 = 2 nC / m2. Determine the strength of the electrostatic field: 1) between the planes, 2) outside the planes. Build a graph of the field strength along a line perpendicular to the planes.