polar

polar wandering

Migration of the magnetic poles of the Earth through geologic time. Scientific evidence indicates that the magnetic poles have slowly and erratically wandered across the surface of the Earth. Pole locations calculated from measurements on rocks younger than about 20 million years do not depart from the present pole locations by very much, but successively greater “virtual pole” distances are revealed for rocks older than 30 million years, indicating that substantial deviations occurred. Calculations of polar wandering formed one of the first important pieces of evidence for continental drift.

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Electrostatic attraction between oppositely charged ions in a chemical compound. Such a bond forms when one or more electrons are transferred from one neutral atom (typically a metal, which becomes a cation) to another (typically a nonmetallic element or group, which becomes an anion). The two types of ion are held together by electrostatic forces in a solid that does not comprise neutral molecules as such; rather, each ion has neighbours of the opposite charge in an ordered overall crystalline structure. When, for example, crystals of common salt (sodium chloride, NaCl) are dissolved in water, they dissociate (see dissociation) into two kinds of ions in equal numbers, sodium cations (Na+) and chloride anions (Cl). Seealso bonding; covalent bond.

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Polar bear (Ursus maritimus).

White semiaquatic bear (Ursus maritimus) found throughout Arctic regions, generally on drifting oceanic ice floes. A swift, wide-ranging traveler and a good swimmer, it stalks and captures its prey. It primarily eats seal but also fish, seaweed, grass, birds, and caribou. The male weighs 900–1,600 lbs (410–720 kg) and is about 5.3 ft (1.6 m) tall at the shoulder and 7–8 ft (2.2–2.5 m) long. It has a short tail. The hairy soles of its broad feet protect it from the cold and help it move across the ice. Though shy, it is dangerous when confronted.

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Any of several northern dogs, including the chow chow, Pomeranian, and Samoyed, characterized by a dense, long coat, erect pointed ears, and a tail that curves over the back. In the U.S., the name is often given to any small, white, long-haired dog; it is also used for the American Eskimo dog. European breeds include the Finnish spitz, with a bright reddish brown coat, and the Lapland spitz, which has a white, brown, or blackish coat.

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(born Feb. 10, 1950, Modesto, Calif., U.S.) U.S. swimmer. He swam in college for Indiana University. At the 1968 Olympic Games he won two gold medals in team relay races. In the 1972 Olympics he won four individual men's events (setting world records in all four) and three team events (one world record); Spitz's feat of winning seven gold medals in a single Olympic Games remains unmatched.

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(born Feb. 10, 1950, Modesto, Calif., U.S.) U.S. swimmer. He swam in college for Indiana University. At the 1968 Olympic Games he won two gold medals in team relay races. In the 1972 Olympics he won four individual men's events (setting world records in all four) and three team events (one world record); Spitz's feat of winning seven gold medals in a single Olympic Games remains unmatched.

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Polar is a town in Langlade County, Wisconsin, United States. The population was 995 at the 2000 census.

Geography

According to the United States Census Bureau, the town has a total area of 35.9 square miles (93.1 km²), of which, 35.6 square miles (92.2 km²) of it is land and 0.3 square miles (0.9 km²) of it (0.95%) is water.

Demographics

As of the census of 2000, there were 995 people, 354 households, and 281 families residing in the town. The population density was 28.0 people per square mile (10.8/km²). There were 383 housing units at an average density of 10.8/sq mi (4.2/km²). The racial makeup of the town was 98.49% White, 0.10% African American, 0.40% Native American, 0.10% Asian, 0.20% from other races, and 0.70% from two or more races. Hispanic or Latino of any race were 0.30% of the population.

There were 354 households out of which 38.4% had children under the age of 18 living with them, 68.1% were married couples living together, 6.5% had a female householder with no husband present, and 20.6% were non-families. 17.8% of all households were made up of individuals and 7.3% had someone living alone who was 65 years of age or older. The average household size was 2.81 and the average family size was 3.17.

In the town the population was spread out with 29.9% under the age of 18, 5.3% from 18 to 24, 29.9% from 25 to 44, 22.4% from 45 to 64, and 12.4% who were 65 years of age or older. The median age was 37 years. For every 100 females there were 102.2 males. For every 100 females age 18 and over, there were 106.2 males.

The median income for a household in the town was $41,477, and the median income for a family was $48,083. Males had a median income of $31,625 versus $22,059 for females. The per capita income for the town was $17,141. About 3.7% of families and 7.0% of the population were below the poverty line, including 11.0% of those under age 18 and 6.0% of those age 65 or over.

References

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