Why does jello jiggle on a plate?

1. Gel Structure: Jello is a colloid, meaning it consists of a solid dispersed throughout a liquid. In this case, the solid is gelatin, a protein that forms a network of long chains. These chains are intertwined and hold water molecules, creating a gel structure.

2. Elasticity: The gelatin network in jello is elastic, meaning it can stretch and return to its original shape. When you apply pressure (like jiggling) to the jello, the gelatin network deforms. Because of its elasticity, it springs back to its original form, causing the jiggling motion.

3. Water Content: Jello contains a significant amount of water, which allows for the gelatin network to move freely. The water acts as a lubricant, enabling the gelatin chains to slide past each other and deform easily.

4. Viscosity: Jello has a high viscosity, which means it resists flow. This viscosity contributes to the springy and jiggly texture.

In summary: Jello jiggles due to the combination of its gelatin network, elasticity, water content, and viscosity. This unique structure allows it to deform under pressure and then return to its original form, creating the familiar jiggly motion.