By filling a glass completely with water, covering it with a piece of stiff paper, and inverting it, the paper stays in place and holds the water inside the glass.

1. Fill a drinking glass completely to the brim with water. (If the glass is not full, the experiment won’t work.)
2. Place a stiff sheet of paper (such as poster board) over the mouth of the glass.
3. Move the glass over a sink or large container to prevent spills.
4. Hold the paper firmly against the glass with one hand and quickly invert the glass.
5. Remove your hand from the paper. Observe how the paper stays in place, preventing the water from falling.

Upside Down Water Glass Science Experiment - Cool Science Experiments Headquarters:

upside down water glass physics - Homemade Science with Bruce Yeany:

📄 Upside Down Glass of Water Science Experiment - Cool Science Experiments Headquarters: https://coolscienceexperimentshq.com/upside-down-glass-of-water-experiment/

• Try using different types of paper (thin paper, cardboard, or plastic sheets) and compare results.
• Test with different glass sizes and amounts of water.
• See how long the paper can hold before becoming saturated and falling.
• Add food coloring to the water for visual effect.

• Perform over a sink or container to catch spills.
• Use sturdy paper to avoid sudden collapse.
• Handle the glass carefully to avoid dropping and breaking.

• Why doesn’t the water fall out of the glass when upside down?
• What role does air pressure play in holding the paper in place?
• How heavy is the air pressing upward compared to the weight of the water?
• Why does the paper eventually fall after a while?
• Can you think of real-world examples where air pressure prevents liquids or gases from escaping?