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Convection Current Experiment Using Teabags

Lizzy Choi

Almaty International School

Purpose of experiment

The key to this experiment is the illustration of the concept of convection currents, which are movements of fluids. In this case, the fluid is air, whose movement is caused by temperature differences. The density of air depends on its temperature. The higher the temperature, the less dense the air is. Therefore, the warm, less dense air rises while the cooler and denser air sinks down.

Figure 1. Ignition of tea bag

Ignition: When the tea bag is lighted, the heat causes the air inside the bag to warm up. As the air heats up, it expands in volume.

Figure 2. Initiation of convection currents

Convection Currents: The warm air inside the tea bag is now lighter and less dense than the cooler air outside the bag. This temperature difference sets up a convection current: the warm air rises, creating an updraft, while cooler air flows in to replace it

from the surroundings.

Figure 3. Lift-off of teabag

Lift-off: The warm air becomes strong enough to overcome the gravitational pull on the tea bag. This creates the illusion that the tea bag is floating or levitating.

Stabilization: The tea bag continues to burn, providing a continuous source of heat. It is important to note that this experiment works because the tea bag is lightweight and that is sufficient to overcome gravity. The experiment demonstrates a basic

principle of fluid dynamics and heat transfer.


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