/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 42 Explain how an ice skate interac... [FREE SOLUTION] | 91影视

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Chapter 2: Problem 42

Explain how an ice skate interacts with the ice surface. What mechanism acts to reduce sliding friction between skate and ice?

Short Answer

Expert verified
The primary mechanism that acts to reduce sliding friction between skate and ice is the pressure-induced melting of ice. As pressure increases, so does temperature, resulting in the ice beneath the skate blade turning into a thin layer of water. This layer provides lubrication, thus reducing friction. It's also due to the 'Leidenfrost' effect, which causes the melted water to remain in a liquid state longer, further reducing friction.

Step by step solution

01

Understanding the process

Ice skating takes advantage of the principles of physics, mainly pressure and heat exchange. The first step in comprehending this mechanism is to understand that the blade of the skate when pressured upon the ice surface causes a thin layer of the ice to melt. This layer, called the 'lubricating layer', allows the skate to move smoothly over the ice. This is due to the increase in pressure which in turn raises the temperature of the ice, leading it to melt.
02

Role of the ice surface

Now, think of the ice surface. It isn't completely flat. The ice has tiny valleys and peaks, which increase friction. But, as the thin layer of water forms due to the pressure exerted by the skate, these irregularities on the ice surface are filled in, allowing a smoother glide.
03

The 'Leidenfrost' effect

The last step to understanding this is to learn the 'Leidenfrost' effect, a phenomenon in which a liquid produces an insulating vapor layer keeping that liquid from boiling rapidly due to the layer鈥檚 insulative quality. It is this phenomenon that causes the melted ice to remain liquid for longer periods, which further facilitates a smooth glide on the surface.

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