The key to pouring water very quietly from a teapot is not just holding the spout close to the cup, but creating a perfectly smooth stream of liquid.
Mouad Boudina at Seoul National University in South Korea drinks tea every morning. Repeatedly pouring tea into a cup from a traditional teapot from his hometown in Morocco made him wonder what makes this process noisy. To find out, he and his colleagues experimented with pouring water in the lab.