How can you show that liquids transfer heat by process of convection?

Answer 1

-- Take a glass of water. Set it aside or put it in the fridge.

-- Take another glass of water. Mix some food coloring into it, then put it in the

microwave or in the oven for a short time. It doesn't have to boil, just warm it up.

-- Put a straw down into the glass of cool, colorless water.

-- Dribble some of the warm, colored water into the straw.

The warm, colored water runs down inside the straw, and comes out on the bottom

of the cool, colorless water. It just lays there for a few seconds, then it starts rising

to the top, carrying heat with it. You can see exactly how it's moving, because

wherever the warm water goes, the color goes.

Now you can see how a pot of water gets heated through and through on the stove,

and you can understand why we put the fire under the pot and not on top of it.