Today we did a simple experiment to show convection currents. Convection is the movement of heat in a fluid, which can be a liquid or a gas, but not a solid.
Examples of convection currents:
- in weather, when warm air and cold air meet – warm air rises, cool air falls.
- in cooking liquids such as soup – soup on the bottom of the pan gets warm and rises, and at the top cooler soup falls
In order to see this movement of heat, you can do this simple experiment.
Note: Adult help needed
2 glass bottles
hot tap water
cold tap water
Piece of thin cardboard
Dish or tray in case of spills
1. Pour hot tap water into one of the glass bottles
2. Pour cold tap water into the other glass bottle
3. Add food coloring. We added food coloring to only one bottle, the hot water, but Steve Spangler Science shows a video of this experiment using 2 colors.
3. Place the cardboard over the mouth of the bottle of cold water, carefully flip over while holding the card onto the bottle of warm water.
4. Slowly pull the card out from between the bottles.
5. Observe. The hot water rises into the bottle containing the cold water.