College of Liberal Arts & Sciences
8A05.30 - Eratosthenes' Measurement of Earth's Radius
Place the model so that one of the pillars is pointed at the light source and gives no shadow. Bend the cardboard and show that the other pillar produces a shadow whose size depends on the radius you have produced by bending the cardboard.
- Terrence Toepker, "A Balloon in the Sky", TPT, Vol. 61, #5, May 2023, p. 324.
- Clinton Lewis, "A Tale of Two Bridges and a Round Earth", TPT, Vol. 60, #7, Oct. 2022, p. 614.
- Paul Hewitt, Figuring Physics, TPT, Vol. 58, #8, Nov. 2020, p. 607.
- Carl E. Mungan, "Sizing Up Earth with a Pair of Sticks", TPT, Vol. 57, #8, Nov. 2019, p. 516.
- Paul G. Hewitt, "Pair-of-Sticks Hypothesis", TPT, Vol. 56, #9, Dec. 2018, p. 579.
- Paul Hewitt, "Solution to the September 2018 Figuring Physics", TPT, Vol. 56, #7, Oct. 2018, p. 483.
- "Erratum: to February 'Figuring Physics' Answer", TPT, Vol. 56, #4, Apr. 2018, p. 197.
- Paul Hewitt, "Answer to February 2018 Figuring Physics", TPT, Vol. 56, #3, Mar. 2018, p. 160.
- Rondo N. Jeffery, "Observing Earth From Above, Again", TPT, Vol. 52, #2, Feb. 2014, p. 69.
- J. Mottmann, "The Size of Earth from Seven Miles Up", TPT, Vol. 51, #9, Dec. 2013, p. 555.
- Seihi Takemae, Peter Kirwin, and Gordon McIntosh, "Reproducing Eratosthenes' Determination of Earth's Circumference on a Smaller Scale", TPT, Vol. 51, #4, Apr. 2013, p. 222.
- Ronald A. Brown and Alok Kumar, "A New Perspective on Eratosthenes' Measurement of the Earth", TPT, Vol. 49, #7, Oct. 2011, p. 445.
- Silvia Pugliese Jona, "Eratosthenes' Measurement", TPT, Vol. 48, #2, Feb. 2010, p. 84.
- Dhevan Gangadharan, "Measuring the Radius of the Earth from a Mountain Top Overlooking the Ocean", TPT, Vol. 47, #8, Nov. 2009, p. 533.
- Mark L. Biermann and Nicholas A. Nelson, "Using the GPS to Determine the Size of the Earth", TPT, Vol. 38, #6, Sept. 2000, p. 360.
- D. Rae Carpenter, Jr., "Sight Distance at Sea", TPT, Vol. 31, #9, Dec. 1993, p. 519.
- Zachary H. Levine, "How to Measure the Radius of the Earth on Your Beach Vacation", TPT, Vol. 31, #7, Oct. 1993, p. 440.
- Jerry Webb and Roberta Bustin, "Eratosthenes Revisited", TPT, Vol. 26, #3, Mar. 1988, p. 154.
- Rondo N. Jeffery and Richard G. Hills, "Eratosthenes Remembered on United Airlines Flight 456", TPT, Vol. 25, #8, Nov. 1987, p. 500.
- Kevin Krisciunas et al., "The First Three Rungs of the Cosmological Distance Ladder", AJP, Vol. 80, #5, May 2012, p. 429.
- Frank O. Goodman, "Measure the Earth's Radius While Boating on One of its Lakes", AJP, Vol. 61, #4, Apr. 1993, p. 378.
- Dennis Rawlins, "Doubling your Sunsets or How Anyone Can Measure the Earth's Size with Wristwatch and Meterstick", AJP, Vol. 47, #2, Feb. 1979, p. 126.
- Jearl Walker, "The Amateur Scientist: How to Measure the Size of the Earth with Only a Foot Rule or a Stopwatch", Scientific American, Vol. 240, #5, May 1979, p. 172.
- "S-360. Sight Distance at Sea", DICK and RAE Physics Demo Notebook, 1993.
- Christopher P. Jargodzki and Franklin Potter, "359, Measuring the Earth", Mad About Physics, p. 141, 282 - 283.
- Jim Glenn, "The Geometers", Scientific Genius: The Twenty Greatest Minds, p. 18 - 19.
- Robert P. Crease, "Measuring the World: Eratosthenes' Measurement of the Earth's Circumference", The Prism and the Pendulum, p. 2.
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