What you need:
A glass tumbler, a vessel, and water
What you do:
- Fill the glass tumbler and the vessel with water.
- Pour half the water from the glass into the vessel while holding the glass above the vessel.
- Observe what happens. Do bubbles form?
- Gently pour the remaining water in the glass tumbler into the vessel while holding the glass close to it.
- Observe what happens. Do bubbles form now?
What do you see?
Bubbles form on the surface of the water in the vessel when you pour water into the vessel from a height. However, no bubbles form when you pour water into it gently while holding the glass close to the vessel.
Why does this happen?
When you pour water into the vessel while holding the glass close to it, the water falling gently cannot penetrate the ‘skin’ of the water in the vessel. But when you pour the water from a great height, the falling water traps air in the stream, forming air pockets. The stream strikes the water surface with great force. The stream breaks through the ‘skin’ into the water and then air pockets bubble back to the surface.
Picture Credit : Google
