일반물리학 2 — Circuits: Problem 49

49 Side flash. Figure 27-48 indicates one reason no one should stand under a tree during a lightning storm. If lightning comes down the side of the tree, a portion can jump over to the person, especially if the current on the tree reaches a dry region on the bark and thereafter must travel through air to reach the ground. In the figure, part of the lightning jumps through distance \(d\) in air and then travels through the person (who has negligible resistance relative to that of air because of the highly conducting salty fluids within the body). The rest of the current travels through air alongside the tree, for a distance \(h\). If \(d/h = 0.380\) and the total current is \(I = 4000 \text{ A}\), what is the current through the person?