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This February Hopes she'll be showing off her moves at the 2010 Winter Olympic Games in Vancouver, Canada. "I will work quitetough to achieve that aim," says Rachael, among those highest-ranked skaters on earth. When she chooses to the ice, her skates'blades glide easily over the slick surface. https://github.com/skateszone/skate/wiki/How-To-Know-What-Size-Of-Skateboard-Should-I-Need-To-Get

And whether the athlete is landing a reverse or preparing for a twist, ice leaves herwinning hints potential. But how?

Read on to learn.Chill FactorJust like the ice cubes that trendy your Lemonade, the slab of ice beneath Rachael's skates is made up of water molecules. Oxygenmolecule that make up a water molecule share and both hydrogen atoms electrons. "However, the sharing isn't equal," says PaulDoherty, a physicist at the Exploratorium in California. 1 side of the water molecule ends up with the other side and a negativecharge with a one.

This causes water molecules to be attracted to one another. When temperatures are above 0[degrees]C (32[degrees]F), water molecules jiggle and pull these links apart. The result? Liquidwater. However, as the jiggling motion, temperatures dip slows down. Afterward, the water molecules package and may give in to theirappeal. Liquid water turns into ice. That is why the ice Rachael glides over is retained In a teeth-chattering -3[degrees]C (27[degrees]F).

This way, Rachael can showher off spins and jumps without landing in a giant pool of water. Slip-N-SlideGood thing for Rachael that ice is not only But slippery. Skaters would be met with an ear-splitting screech if they attemptedtheir stunts such as concrete or glass on additional solids. Why is ice slippery? Scientists are still puzzling over this question. But physicists understand One thing: The answer given inschool textbooks is incorrect.

 Researchers used to think that a skater's Weight put pressure causing it to melt at a lower temperature. But experimentsdemonstrated that this pressure change is too small to make ice melt. Today, many scientists believe another force Holds the clue: friction that is slick. When her thighs are pumped by Rachael, herskates' blades rub against the ice. This rubbing creates friction, which releases heat. With each leg stroke, the heat warms upthe ice beneath the skater's feet. When the ice's temperature climbs above freezing, then a thin layer on the outside melts intoliquid water (see Why Ice Is Slippery, page 14).

 The water behaves under Rachael's skates to permit for graceful glides twists,and smooth landings. Liquid LayerRachael can never be too careful on the ice rink. Whether she is landing a triple axel or making her final present, there is anopportunity of slipping. May slip. This led scientists to think that there has to be more to ice's slipperiness than rust .

 Scientists have found that ice's surface Is naturally slick. Normally, the water molecules are lined up like cars in a parkinggarage, with neatly ordered vehicles on each floor. But like the automobiles on the floor of the parking garage, the molecules inthe upper layer of ice do not have any molecules above them. "[Molecules at the top layer] are a bit Fleer to maneuver about," Doherty says. These molecules behave more. "The surface issimilar to water and allows the blades to slip," he states.

That is type of skateboards, who expects to Glide across the ice to win a medal from the Olympic Games. Words to KnowMolecule--A set of two or more atoms that By sharing electrons in a chemical 10, are joined together. Electron negative charge. Pressure--A force That's applied against a Gas. Friction--A force which acts against motion when two surfaces rub against each other. WHY ICE IS SLIPPERYMELTING BY FRICTION: A blade that is fast-moving creates friction on the ice. This pressure causes heat, which melts the icecrystals below the skate into a thin layer of water.

However, this reasoning isn't the entire story. It doesn't explain why even aperson standing on ice can slip. BUILT-IN SLIPPERY LAYER:A liquid-like movie is present on the surface of ice. Chains of water molecules along the layer are exposed to atmosphere and arenot able to form solid ice crystals. It's easy to slip on these chains, which vibrate like fluids. Speedy quiz1. When the temperature rises above 0[degrees]C (32[degrees]F), ice varies from a to a.(A) gasoline, solid(B) liquid, solid(C) liquid, gas(D) solid, liquid2.

A water molecule is made of.(A) two hydrogen atoms and an oxygen atom(B) two oxygen atoms and a hydrogen atom(C) electrons(D) ice particles3. Which explanation for the slipperiness of ice is Cited but false? (A) Friction in the skate's blades melts ice. (B) The skater puts pressure on the ice, Causing it to melt. (C) Ice is obviously slippery due to the Layer's structure. (D) None of the aboveANSWERS1. d 2. a 3. bBEFORE READINGSet a PurposeDiscover why ice is slippery and just how the Sports are made by features of this solid that is common like ice skating potential. Background* If you Believe all ice is the same, think again. Water ice can happen as up to 15 crystalline phases of water. Regular ice andsnow fall called hexagonal icehockey, the variety.

Other types can happen under extreme temperature and pressure combinations,either here on Earth or on other planets. * Hexagonal ice gets its name due to the fact The water molecules line up in a pattern. All snowflakes have six sides, that's. Discussion Question* Have you ever slipped on ice? Can you reduce Your chances of slipping by wearing certain kinds of shoes? How do you think thisworks?

(Answers will vary, but should comprise that boots with ridges for traction would reduce one's likelihood of slipping onice since the ridges increase friction, maintaining the shoe from slipping away from under you.) AFTER READINGDiscussion QuestionFor a tong time, scientists thought in the Incorrect explanation to the question, "Why is ice slippery?"

What are some examples ofscientists finding new concepts to replace erroneous beliefs? (Possible responses: Scientists used to think the sun revolved roundthe Earth before the discovery that it is the other way around; scientists used to think that heavier objects fell faster thanlight ones before it had been demonstrated that gravity accelerates all objects at the exact same pace.) RESOURCE* Ice and People, by Nikki Bundey (Carolrhoda Publications, 2000).

This book reviews what ice hockey is and how animals and peopledeal with cold and ice. Directions: Match the word(s) from the left Column with the correct phrase. 1. Pressure a. The particle within negative charge. 2. Molecule b. A force that acts against movement when two surfaceRub against each other.3. Electron c. A group of two or more atoms which are joinedtogether by sharing electrons At a chemical bond. 4. Friction d. A force That's applied against a gas, Fluid, orsolid. what size skateboard should I get linkedin.com