일반물리학 2 — Gauss' Law: Problem 20

20 Figure 23-31 shows cross sections through two large, parallel, nonconducting sheets with identical distributions of positive charge with surface charge density \(\sigma = 2.31 \times 10^{-22} \text{ C/m}^2\). In unit-vector notation, what is \(\vec{E}\) at points (a) above the sheets, (b) between them, and (c) below them?