Water on a tightrope

Globule wonders...

Can water slide down a string?

Experiment: Water on a tightrope

Hypotheses: Ask children if they think water can slide down a string without falling off. How could this be possible?

Material:

• • One disposable paper drinking glass per child

• • String (approximately 30 cm per child)

• • Water

• • A sharp object

• • A bucket

Manipulation:

1. 1. Ask your early childhood educator to punch a hole near the edge of your glass using the sharp object.

1. 2. Thread the string through the hole and tie a knot inside the glass to secure it.

1. 3. Fill the glass with water, stopping just under the hole.

1. 4. Deposit the empty bucket on the floor.

1. 5. Ask your early childhood educator to tie the other end of the string to your index finger.

1. 6. Place this hand over the bucket and, with your other hand, tighten the string to create a slope by holding the glass higher.

1. 7. Gently incline the glass so the water can slide down the string and fall in the bucket.

Explanation: The water molecules bond together as if they are all holding hands to avoid falling off the string. Cohesion is created between the molecules at the surface. This is called surface tension.

Another way to observe this phenomenon is to fill a glass with water, right to the edge, and to gently continue to add water until a bubble that seems to be slightly higher than the edge of the glass appears.

Angélique Boissonneault

has a Bachelor's Degree in Biological Science. She has worked in a laboratory and tested her knowledge. She has taught Math, Chemistry, and Physics. She has also developed a simplistic and innovative approach designed to introduce young children to scientific experiments, old and new. She created her friend Globule. This character is sometimes red, and sometimes white. He guides little ones through their scientific experiments and discoveries. It is clear to see Angélique is passionate about children and science. Globule's Approach.