Mysterious Rising Water
Watch water defy gravity and move upward.
What you need:
- short, fat candle about 1 to 2 inches high and 1 to 2 inches wide
- plate
- wide-mouth jar
- measuring cup
- tap water
- matches
What do you do?
- Put the plate on the table.
- Pour enough water to cover the bottom of the plate.
- Place the unlit candle in the middle of the plate.
- Cover the candle with the jar.
- What happened?
- Remove the jar and light the candle.
- Watch the candle burn for 2 minutes.
- Place jar over the candle again.
How does it work?
When the jar covered the candle, the candle heated up the air. Hot air expands and pushed out some of the air in the jar.
Oxygen is used up when anything burns. When the candle used up the air (Oxygen) inside the jar, the fire went out. The air cooled down and contracted. At that point, there is less air pressure inside the jar than outside (a vacuum was created). The outside air pushes the water into the jar until the pressure inside the jar is the same as the pressure outside of the jar.
