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Quick Quiz

The amplitude of a wave is a measure of its

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Module of the day

The Hydrologic Cycle

Powered by the sun, water constantly cycles through the Earth and its atmosphere. This module discusses the hydrologic cycle, including the…

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Term of the day

Fick, Adolf

[person] German physicist and physiologist (1829-1901) born in Kassel, Germany. Building upon the work of Thomas Graham, Fick introduced the notion…

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