Video and lesson investigations on the topic of surface tension. Key concepts include:

• Water clings to itself as if it has a ‘skin’.
• The water molecules are strongly attracted to each other, and have a tendency to stay together.
• This is why water forms globules or drops, flows in streams, and appears to have a ‘surface skin’.
• Water behaves differently in spacecraft conditions than it does on Earth.
• In a spacecraft objects do not fall but float.
• On Earth, the force of gravity pulls on a globule of water so that it falls in the shape of a drop.
• In a spacecraft, the effects of gravity are lessened and water tends to remain in the shape of globules.