The pressure of the wire will cut a clean line through the ice (which will freeze back together once the wire passes through, a process called "regelation").
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Classic experiment involving regelation of an ice block as a tensioned wire passes through it. Regelation is the phenomenon of melting under pressure and refreezing when the pressure is reduced. We can demonstrate regelation by looping a fine wire around a block of ice, with a heavy weight attached to it. The pressure exerted on the ice slowly melts it locally, permitting the wire to pass through the entire block.
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Ice skating is given as an example of regelation; however the pressure required is much greater than the weight of a skater. Additionally, regelation does not explain how one can ice skate at sub-zero (°C) temperatures.White, James. The Physics Teacher, 30, 495 (1992).
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Despite the regelation of Deportivo to the Segunda B the striker decided to stay at the club.
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Regelation played a key role in Tyndall's explanation. Forbes didn't see regelation in the same way at all. Complicating their debate, a disagreement arose publicly over who deserved to get investigator credit for what. Articulate friends of Forbes, as well as Forbes himself, thought that Forbes should get the credit for most of the good science, whereas Tyndall thought the credit should be distributed more widely.
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Scientific theories about snowball formation began with a lecture by Michael Faraday in 1842, examining the attractive forces between ice particles. An influential early explanation by James Thomson invoked regelation, in which a solid is melted by pressure and then re-frozen.
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Regelation was discovered by Michael Faraday. It occurs only for substances such as ice, that have the property of expanding upon freezing, for the melting points of those substances decrease with the increasing external pressure. The melting point of ice falls by 0.0072 °C for each additional atm of pressure applied. For example, a pressure of 500 atmospheres is needed for ice to melt at −4 °C.
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General topology (left); dirt-bands in glacier (right). In the Alps, Tyndall studied glaciers, and especially glacier motion. His explanation of glacial flow brought him into dispute with others, particularly James David Forbes. Much of the early scientific work on glacier motion had been done by Forbes, but Forbes at that time didn't know of the phenomenon of regelation which was discovered a little later by Michael Faraday.
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As it became clear that glaciers behaved to some degree as if the ice were a viscous fluid, it was argued that "regelation", or the melting and refreezing of ice at a temperature lowered by the pressure on the ice inside the glacier, was what allowed the ice to deform and flow. James Forbes came up with the essentially correct explanation in the 1840s, although it was several decades before it was fully accepted.
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James Thomson is known for his work on the improvement of water wheels, water pumps and turbines. Also his innovations in the analysis of regelation, i.e., the effect of pressure on the freezing point of water, and his studies in glaciology including glacier motion, where he extended the work of James David Forbes. He studied the experimental work of his colleague Thomas Andrews, concerning the continuity of the liquid and gaseous states of matter, and strengthened understanding of it by applying his strong knowledge of thermodynamics.
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Therefore, there is a continuous replenishment of water flowing from the warm side to the cold side of the particle, and continuous melting to re- establish the thicker film on the warm side. The particle migrates downwards toward the warmer soil in a process that Faraday called "thermal regelation." This effect purifies the ice lenses as they form by repelling fine soil particles. Thus a 10-nanometer film of unfrozen water around each micrometer- sized soil particle can move it 10 micrometers/day in a thermal gradient of as low as 1 °C m−1.
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' One winter day he took Davy to the Larigan River,The Larigan, or Laregan, river is a stream in Penzance. To show him that rubbing two plates of ice together developed sufficient energy by motion, to melt them, and that after the motion was suspended, the pieces were united by regelation. It was a crude form of analogous experiment exhibited by Davy in the lecture-room of the Royal Institution that elicited considerable attention. As professor at the Royal Institution, Davy repeated many of the ingenious experiments he learned from his friend and mentor, Robert Dunkin.
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The wire's track will refill as soon as pressure is relieved, so the ice block will remain solid even after wire passes completely through. This experiment is possible for ice at −10 °C or cooler, and while essentially valid, the details of the process by which the wire passes through the ice are complex. The phenomenon works best with high thermal conductivity materials such as copper, since latent heat of fusion from the top side needs to be transferred to the lower side to supply latent heat of melting. In short, the phenomenon in which ice converts to liquid due to applied pressure and then re-converts to ice once the pressure is removed is called regelation.
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He scored his first goal for River in the ninth round of the Apertura in the 86th minute to earn a 2–2 draw for his club, a header to draw with Banfield. He scored his second goal for the club in 1–0 win over Olimpo in round 16, another header. He scored his third goal in the final round of the Apertura in 4–1 victory over Lanús. During the Clausura he was often criticized for its poor performances and poor form, during the promotion against Belgrano he created a penalty which would later be influtial in River Plate regelation to Nacional B. Despite criticism of River Plate fans, Román was still included in the Nacional B squad but manager Matías Almeyda only used him during a 2–0 defeat against Atlético Tucumán in November 13.
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