Why is tea cooled more rapidly by blowing on it?

Blowing on hot tea does not cool it more rapidly. In fact, it might actually slow down the cooling process.

* Convection: When you blow on hot tea, you are essentially replacing the warm air around the tea with cooler air. This process is called convection. However, convection is actually a relatively slow process. It is much slower than conduction, which is the transfer of heat between two objects in contact with each other.

* Evaporation: Blowing on hot tea does cause some evaporation to occur. However, evaporation is only a significant cooling mechanism for liquids that have a high surface area, such as water droplets. Tea does not have a high enough surface area for evaporation to be a major cooling factor.

In addition to these factors, blowing on hot tea can actually introduce heat into the tea. This is because the air you blow out is likely to be warmer than the tea itself. So, blowing on hot tea may actually make it hotter, not cooler.

Therefore, if you want to cool down your hot tea, it is best to let it sit undisturbed. This will allow the heat to dissipate naturally through conduction and radiation.