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Quick Quiz

Earth's magnetic field is constant.

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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

First Law of Thermodynamics

[noun] One of three Laws of Thermodynamics, or laws relating to heat power. The First Law explores the conservation of energy. Specifically,…

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