1. The problem statement, all variables and given/known data Figure (a) shows three plastic sheets that are large, parallel, and uniformly charged. Figure (b) gives the component of the net electric field along an x axis through the sheets. The scale of the vertical axis is set by Es = 8.4 × 105 N/C. What is the ratio of the charge density on sheet 3 to that on sheet 2? 2. Relevant equations E = σ / 2ε0 3. The attempt at a solution I know that the field between 1 and 2 is three times less strong as that between 2 and 3. 3E12 = E23 Not sure where to go from there. Thanks in advance!