Spinning Eggs

Let's take a look!

Watch the video on YouTube.

Experimental procedure and explanation:

• Prepare a raw and a boiled egg.
• You cannot tell one from the other merely by observing them.
• However, you can easily distinguish them by spinning them on a table.
• When spun by hand, the one that starts to spin easily is the boiled egg, while the one that does not spin as much is the raw egg.
• A boiled egg completely solid, and by spinning the outside, all the inner content spins as a single object.
• The inner content of the raw egg is liquid and can deform. When you spin the outside, the inner content will not instantly start to spin.
• Spin the raw egg several times, and then instantaneously stop the spin by hand. If you let go immediately after you stop it, the egg will start to spin again. This is because the inner content does not stop spinning immediately, even when the outside has stopped.
• The above experiment thus proves that fluids (liquids and gases) deform freely.

[Keywords]	deformation of fluid
[Reference]	“The Wonders of Flow,” Japan Society of Mechanical Engineering, Koudansha Blue Backs, pp. 12-15