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We create and provide high-quality, accessible, educational content in the science, technology, engineering and mathematics (STEM) disciplines at the introductory undergraduate level.

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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 Practice of Science

Scientists use multiple methods to investigate the natural world and these interconnect and overlap, often with unexpected results. This module gives…

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Term of the day


[noun] Magnitude; a measure of height from the highest to lowest point on a vertical axis; a measure of the size of…

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