What have you seen floating or jumping on the surface of the water?
Step 1 Materials
- Paper
- Pens
- Scissors
- A large flat container
- Water
- Wool yarn
- Soap
- Two plastic cups
Step 2 Implementation
Let’s start by preparing the flowers.
- Draw a flower on a piece of paper with a middle part larger than the petals.
- Cut out the flower from the paper. The flower can be decorated with crayons.
- Fold the flower petals inwards in order.
- Think about: Will the flower float in the water.
- Place the flower into the water.
- Think about: Why are the flowers opening up in the water?
Step 3: Why
The flower opening is a capillary effect. The structure of the paper has small tubes through which water can penetrate to travel upwards. This makes the flowers open the petals.
Step 4 Implementation
What happens to wool yarn if it is put in a plastic cup with water.
- Use two different plastic cups, one with only water, the other with some added soap.
- What is happening? Why?
Step 5: Why
The soap reduces the surface tension of the water and causes the wool yarn to become wetter and sink. to the bottom of the earth.