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Why doesn't a wire simply cut a block of ice in two when it passes through the ice? Pressure beneath the wire melts the ice without warming it, so the liquid flows above the wire, where it refreezes at lower pressure.

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Answer:

This phenomenon is known as the "regelation effect," which occurs when ice melts under pressure and then refreezes when the pressure is reduced. When a wire is pushed through a block of ice, the pressure exerted by the wire on the ice causes the ice to melt locally, allowing the wire to pass through. As the wire moves forward, the pressure is relieved, and the melted ice refreezes behind the wire, effectively sealing the cut.

The key point to note here is that the pressure exerted by the wire on the ice is localized and does not result in a significant increase in temperature. The melting occurs only in the immediate vicinity of the wire, and the rest of the ice block remains frozen. The heat required for melting the ice is supplied by the wire, which becomes slightly warmer as it passes through the ice. However, the amount of heat transferred is negligible and does not cause a significant rise in temperature.

Overall, the regelation effect is a result of the unique properties of ice, and it allows for the efficient cutting of ice blocks using wires or other tools.

Step-by-step explanation:

User Jeff McClintock
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