Experimenting with Capillarity

While most students know that plants need water to grow, they don't understand how the water is taken from the ground and distributed throughout the flower. Angelique Boissonneault, an EducatAll.com contributor, provides a great experiment for student's discovery of capillarity.

To begin, ask children to hypothesize how plants get water. Do the petals, stem, etc. soak up rain water that falls on them? Do they get water from the ground? What happens to a plant that doesn't get enough water? After they have theorized about plants and water, collect the following materials: paper, pencils, scissors for kids, and a container of water. Have your students draw a four-petal flower onto their piece of paper and use scissors to cut it out. Instruct your students to fold the petals of the flower upward, like that of an unopened flower. Invite your students to put their flowers on the surface of the water and observe what happens.

While paper might seem solid and smooth, in reality, it is made up of tiny fibers that are woven together. In addition to this, paper fibers and water are attracted to each other. When the flower is set on the water, the water will begin to 'climb' up the paper petals, filling the fiber holes until they become to heavy, and the flower 'blooms'. The lesson: real flowers are also made up of individual fibers which receive water in this same fashion. Students will be fascinated with this concept of capillarity.

Capillarity - Educatall