科学素养与生活应用·英语30篇（2）

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避雷针并不吸引雷电，而是提供安全放电路径

Lightning rods do not increase the chance of a strike—they simply offer the easiest path to ground.
Their pointed tip enhances local electric field strength, encouraging ionization of surrounding air molecules.
Once ionized, air becomes conductive and forms a preferential channel for lightning’s downward leader.
Copper or aluminum rods connect via low-resistance cables to deeply buried grounding rods.
This system safely directs massive current around structures instead of through flammable materials.
Proper installation requires grounding resistance below 25 ohms to prevent side flashes or voltage surges.
Rods protect a conical zone extending outward at a 45-degree angle from the tip.
Modern buildings often integrate meshed conductors into roofs for more uniform protection coverage.
Surge protectors work alongside rods to shield electronics from induced voltage spikes.
Without such systems, lightning could explode bricks, shatter concrete, or ignite gas lines instantly.