What you need:
A glass and a vessel with tea What you do:
Hold the vessel high above the glass and pour the tea into it. What do you find? Bubbles form on the surface of the tea inside the glass. Next hold the vessel close to the glass and pour the tea into it.
What do you find?
Bubbles don’t form on the surface of the tea inside the glass.
What’s the reason?
Due to surface tension, the surface of a liquid behaves like a stretched membrane or skin’. When you pour tea into the glass while holding the vessel close to it the tea falling gently cannot penetrate the skin of the tea in the vessel. But when you pour it from a great height, it strikes the surface of the tea in the glass with great force. The skin breaks trapping air, which bubbles back to the surface.
Picture Credit : Google
