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Radio Inquiry Unit
Radio Inquiry Unit While serving in the U.S. Army during World War I, Armstrong synthesized three ideas to create his superheterodyne circuit for selectively amplifying a very high fr…
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Radio Inquiry Unit
Radio Inquiry Unit According to the E.H. Armstrong, wireless receiving system patent, “The present invention relates to improvements in the arrangement and connections o…
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Radio Inquiry Unit
Radio Inquiry Unit From the Rare Book & Manuscript Library, Columbia University Visit Source Download PDF …
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Hands-on Activity
Skyscrapers Inquiry Unit
Skyscrapers Inquiry Unit Download PDF Skyscrapers Hands-On Activity Prompt for the students: Using only the materials provided, teams of students will design and build a structure as tall as p…
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Inquiry Unit
The symbol of growth in China and India of the early 21st century is the proliferation of skyscrapers. This was also the symbol of urbanization in the early 20th century U.S. How did this come about? …
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Skyscrapers Inquiry Unit
The Pyramid of Cheops or Khufu, constructed c. 2580 – c. 2560 BCE, is the tallest pyramid in Giza and the largest ever constructed in Egypt. Made of limestone and originally reaching a height …
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Skyscrapers Inquiry Unit
Patent, by African American inventor Alexander Miles, for new and useful improvements in elevators. The patent relates to mechanisms for closing the openings to the shafts of passenger and freight ele…
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Inquiry Unit
When was the last time you lived without electric lights? Maybe a thunderstorm, hurricane, or blizzard caused a power outage in your neighborhood. Maybe you live in a village without electric lights. …
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Electric Lighting Inquiry Unit
Photograph of an electric lamp being illuminated by passing a current through the body of Mark Twain. Download PDF Visit Source 1 Visit Source 2…
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Electric Lighting Inquiry Unit
Photographs of Luna Park in Coney Island, NY at night showcasing the spectacular lighting. Download PDF Visit Source…
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