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Why Can We Skate on Ice?

How does ice skating work? As this video explains, the answer is not as easy as it might appear.

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There are a number of theories about how ice skating works. One theory, suggested by Englishman Michael Faraday in 1850, says it is due to pressure. Pressure, the force applied by the weight of the skater to the blades of the skate, reduces the melting point of the ice. As the ice melts slightly under the pressure, it leaves a thin film of water that the blades can glide on. It then refreezes when the pressure is removed. This process is known as regelation . Modern scientists have disputed this pressure theory, however, asserting that even the heaviest human skater would not be able to create enough pressure to bring the ice to its melting point at temperatures colder than 26°F (–3.5°C). Another popular theory says that the answer is friction. The friction theory holds that it is the friction caused by the blade moving against the ice that generates enough heat to produce the

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Series Glossary Of Key Terms: This back-of-the-book glossary cont used throughout this series. Words found here increase the reader’s comprehend high r-lev l books and rticles in this field.

Bruising Winnipeg Jets defenseman Dustin Byfuglien weighs 260 lb., but even he is not heavy enough to create the pressure under his skate blades needed to melt ice.

10 CONNECTING STEM AND SPORTS | ICE HOCKEY