The experimental principle of Rainbow Bridge is capillary phenomenon. Water rises along the capillary, and the gap on the paper towel can be regarded as a capillary, so the pigment solution runs into the empty cup along the paper towel itself.

Children all like beautiful rainbows, but beautiful rainbows are always short-lived. Today, let's do a little experiment about rainbow with mom and dad, so that the rainbow bridge will exist forever! Children cannot operate independently and observe continuously. When providing experiments, parents can let their children interact with materials, provide a variety of materials, and encourage children to explore whether different materials can complete experiments.

The materials we need to prepare are:

1, watercolor pen

2. A basin of water

3. Paper

step

First, we take out our watercolor pen, then open the paper towel and use our watercolor pen to paint several colors we like on the bottom of the paper towel. Be sure to apply it gently! Otherwise, the tissue will rot.

Prepare a basin of clean water, slowly put the colored part of the paper towel into the water, and the Rainbow Bridge will appear. Guide the children to observe, the rainbow bridge appears!

Experimental principle

This is a capillary phenomenon, water will rise along the capillary, and the gap on the paper towel can be regarded as a capillary, so the pigment solution will run into the empty cup along the paper towel itself.