How Strong are Eggshells?

Introduction

Have you ever seen an arch structure in a building, such as over a doorway or surrounding large windows? Arches have been used in structural engineering since ancient times. In this activity you will test the strength of a naturally occurring arch shape: the shell of an egg. So grab some eggs and put them to good engineering use in trying to answer the following question: Just how much mass can an eggshell can support?

Credits

Materials

• Raw eggs (at least 3)
• A bowl
• Dinner plate or other large, flat surface to place eggshells on for testing
• Pencil or marker
• Optional: Ruler
• A rotary tool, sometimes called a dremel, similar to Amazon.com. Alternatively it is possible, but more challenging, to use a small triangular file.
• Safety goggles, to protect your eyes from bits of egg shell when using the rotary tool
• Hardcover book
• Several magazines or light-weight books