The small hole at the top of a teapot serves two main purposes:
-
Balancing Air Pressure: The hole helps regulate the air pressure inside and outside the teapot, ensuring that the internal pressure equals the external atmospheric pressure. This allows water to flow out smoothly.
-
Preventing Vacuum Lock: By allowing air to enter the teapot, the hole prevents a vacuum from forming when pouring tea, which would otherwise stop the water from flowing out.
These two functions ensure the teapot operates properly and remains convenient to use.
