일반물리학 2 — Gauss' Law: Problem 12

12 Figure 23-28 shows a section of a long, thin-walled metal tube of radius \( R = 2.50 \text{ cm} \), with a charge per unit length of \( \lambda = 2.00 \times 10^{-8} \text{ C/m} \). What is the magnitude \( E \) of the electric field at radial distance (a) \( r = R/2.00 \) and (b) \( r = 2.00R \)? (c) Graph \( E \) versus \( r \) for the range \( r = 0 \) to \( 2.00R \).