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CopperCicada · M
Jello is a gel, more specifically a hydrogel. That means it’s a matrix of cross linked material with water in the spaces.
It’s not really like a liquid, as the cross liked solid prevents fluid flow. Fluids have what is called no shear modulus, so they can’t support shear strain. Which is why they just pour everywhere.
It’s more like a solid in that it does have sheer modulus, though a small one. When the jello warms the sheer modulus decreases and so cubes of jello get floppy and turn to liquid.
It’s not really like a liquid, as the cross liked solid prevents fluid flow. Fluids have what is called no shear modulus, so they can’t support shear strain. Which is why they just pour everywhere.
It’s more like a solid in that it does have sheer modulus, though a small one. When the jello warms the sheer modulus decreases and so cubes of jello get floppy and turn to liquid.
CopperCicada · M
@helenS I was thinking a better answer is that the jello is a colloid, a system where solid bits are suspended in water. A two phase system. What makes it a gel is that at lower temperatures the gelatin bits forms a network that traps the water. Then there is a shear modulus, it can “stand up”. Raise the temperature and the network falls apart and you have a simple colloid. Viscous liquid of solid bits in water.