Inertia of an Egg
According to Newton's first two laws of physics, inertia is the tendency of all objects (or matter) to remain still if it is still or, if moving, keep moving at a constant rate and in a constant direction unless acted on by an external force. The external force can be anything from friction and gravity to human intervention.
In this fun science fair project from Science Fair Projects World, students will use eggs to explore the concept of inertia. To begin, students are presented with this problem:
A dozen eggs are placed on glass plates and set on a table. Hidden among the raw eggs is one hard-boiled egg. How can the hard-boiled egg be identified without picking up any of the eggs and without cracking any of their shells?
Students should brainstorm ideas, but will ultimately be led to compare the inertia of each egg by spinning them on the plate. Students will discover that the liquid properties of the raw eggs produce a much different effect on the eggs inertia than the solid property of the hard-boiled egg. The presence of these 'external forces' will ultimately lead to the discovery of the hard-boiled egg.