ESBOCES Students Learn about Friction by Studying Ancient Egypt
How Was Friction Reduced to Move Stones across the Sand to Build the Pyramids?
To help his students better understand the relationship between sand and friction, Special Education Teacher Salvatore Guastella took his class at Westhampton Beach Learning Center back in time to ancient Egypt. Guastella devised an experiment to discover how the ancient Egyptians moved those enormous blocks of stone across the sand to build the pyramids.
The ancient Egyptians used sleds to transport stone because the wheel had not yet been invented. (Interesting note: The wheel was invented approximately 3,500 years ago, after the time the pyramids were built.) Guastella asked his class, “How did they do it without modern machinery?”
His experiment involved sand, a storage container, twine, a foam tray, a brick, and water. Guastella tied the brick to an ordinary foam takeout tray with twine and pulled it across a large storage container filled with sand. The class assisted and watched in person and remotely while the experiment was performed three times, moving the brick over dry, damp, and then wet sand to see which scenario experienced the most friction.
Sand quickly accumulated in front of the makeshift sled when it was pulled across the dry sand, slowing it down significantly and making travel the most difficult. The trips across damp sand and then wet sand were greatly improved each time as the sand became more firm and smooth. “The more water you use, the less force you need, which therefore required less people to pull the sleds,” explained Guastella.
Throughout the experiment, students gradually completed a lab packet of information where they stated their hypothesis and answered questions regarding the data and final results.