雅思阅读 111: Electric Rain That Eats Metal

Adapted from 'Electric rain can eat through metal', Scientific American, August 2026.

🎧 课文朗读音频

Reading Passage

Earth weather is suffused with electricity. When particles of ice and hail collide in our atmosphere, they become charged and build up, finally unleashing giant electric sparks as lightning. But even tiny rain droplets can become electrically charged as they fall, and this charge could be enough to eat through metal.

Research published in Nature shows that water droplets become electrified as they move across smooth surfaces. This could help explain why rain corrodes metals even if they have protective coatings. It also answers a long-standing question: why does water take so long to move down smooth surfaces despite the apparent lack of friction?

Hans-Jurgen Butt of the Max Planck Institute for Polymer Research in Germany and colleagues suspected hidden chemistry between the surface and the water. When solids rub against one another, they can create an electric charge. But physicists did not think liquids would behave in a similar way. For a liquid, there is no force that could break a bond, Butt says.

In the study, the team ran water droplets down different surfaces, such as windows and plant leaves, and onto a copper plate with a thin coating of Teflon. The water drops burrowed through the Teflon and into the copper, creating pits. The same effect appeared on metals with other protective coatings. Water that dropped directly onto the plates without running down another surface did not have corrosive power.

After studying the shape of the droplets, researchers believe the water and copper plate create an electric field, with the water taking on a positive charge as it moves down the surface and the metal taking on a negative charge. As the drop nears the metal, the electric field gets stronger. Eventually the field becomes so strong that it breaks down the metal.

Charged rain is not dangerous to humans. But it could help explain why even materials coated with industrial anti-corrosion solutions sometimes fail. The breakdown of infrastructure is a trillion-dollar problem. Doing a better job of controlling corrosion could save money and lives, from pharmaceutical equipment to petrochemical plants to medical implants.

Questions 1-5

Choose the correct letter, A, B, C or D.

1. What did the Nature study find? A. Rain is dangerous to humans B. Water droplets become electrified sliding on surfaces and corrode metal C. Lightning causes all corrosion D. Teflon is not protective
2. Where does Butt work? A. MIT B. Max Planck Institute C. Stanford D. Oxford
3. What happened when water ran down surfaces onto a Teflon-coated copper plate? A. Nothing happened B. The Teflon protected the copper C. The drops burrowed through Teflon into copper, creating pits D. The water evaporated
4. What charge does the water take as it slides? A. Negative B. Positive C. Neutral D. Alternating
5. How serious is corrosion globally? A. A million-dollar problem B. A trillion-dollar problem C. Not a problem D. Only affects houses

Questions 6-10

Do the following statements agree with the information? Write TRUE, FALSE or NOT GIVEN.

6. Charged rain droplets are dangerous to people.
7. Water that drops directly onto metal also corrodes it.
8. The electric field strengthens as the drop approaches the metal.
9. Physicists expected liquids to create electric charge.
10. Corrosion affects medical implants.

Questions 11-13

Complete the summary. Choose ONE WORD ONLY.

Water droplets become 11 as they slide down smooth surfaces. The water takes a positive charge and the metal a 12 charge. When the field is strong enough, it breaks down the 13.

Answers

1. B 2. B 3. C 4. B 5. B
2. FALSE 7. FALSE 8. TRUE 9. FALSE 10. TRUE
3. electrified 12. negative 13. metal

Key Vocabulary

⬅️ 上一篇 ｜ 📚 目录 ｜ 下一篇 ➡️